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59a416cb09d32b3d86cbb27c2e98b3b830e92c7b
65 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
 teamchong
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59a416cb09 |
feat(history): always-on history compression + fix gate-vs-renderer asymmetry
Rip the compressHistory opt-in and run Variant C history-image collapse on
every request that has a closed-prefix run. There is now ONE codepath: no
toggle, no env switch, no per-request opt-in. The reason the option was
defaulted-off was a -250% live measurement on 2026-05-19 (commit
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teamchong
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178fd4af6f |
fix(gate): scale per-image token cost by numCols (close multi-col loss-risk)
Production runs multiCol=2 by default. The pre-flight gate
`isCompressionProfitable()` was using a flat TOKENS_PER_IMAGE=2500
constant at every numCols, so it believed multi-col images were ~2x
cheaper than they actually are and would let net-loss compressions
through on wider canvases.
Replace the flat constant with `effectiveTokensPerImage(numCols)`:
numCols=1: 2500 (empirical, N=33 cold-miss measurement)
numCols>1: 2500 * n * 1.10 (linear extrapolation + 10% margin)
The 10% margin absorbs extrapolation noise — we don't yet have
empirical cost measurements at numCols>=2. Per user constraint
"ok pre-flight gate is ok to be not correct as long as we don't
lose money," every uncertainty resolves in favor of pass-through.
At worst we miss opportunities; we never burn money on net-loss
images.
Test fixtures bumped to match the new break-even (~22k chars at
n=2). Two obsolete cpt-flip tests REWRITTEN to assert the safe
behavior: cpt override flips at numCols=1, but at numCols=2 the
safety margin holds and the slab stays rejected.
Old break-even at default cpt=4:
n=1: ~10k chars (1 image @ 2500 tok == 10k/4 = 2500 text tok)
n=2 [old/wrong]: ~10k chars (same flat cost)
n=2 [new/safe]: ~22k chars (1 image @ 5500 tok == 22k/4 text tok)
Verified: 263/263 tests pass, typecheck clean, build clean.
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teamchong
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dfd3bf514f |
feat(proxy): cache-aware baseline via second count_tokens probe
The baseline_tokens probe alone reports the COLD cost of the unproxied
body — but the user's request actually carries `cache_control` markers
that would have cached on the unproxied path too. Comparing cold-
baseline against warm-actual was an apples-to-oranges inflation of
saved%.
Fix: fire a SECOND count_tokens probe on the body TRUNCATED at the last
`cache_control` marker. Difference between the two is (cacheable_prefix,
cold_tail). Dashboard weights the prefix by the SAME cache class the
actual response landed in:
cacheable = baseline_cacheable_tokens or 0
cold_tail = baseline_tokens − cacheable
weight = cr>0 ? 0.10 (warm hit — both paths cache)
: cc>0 ? 1.25 (cold create — both paths build cache)
: 1.0 (no caching — marker rejected or absent)
baseline_input_eff = cacheable·weight + cold_tail·1.0
actual_input_eff = input + cache_create·1.25 + cache_read·0.10
saved = baseline_input_eff − actual_input_eff
Now the headline number is the exact unproxied counterfactual, not a
cold-every-time approximation. No estimation, no α, no assumptions —
every input is a measurement.
Wiring:
- src/core/proxy.ts: buildCountTokensCacheablePrefix() walks messages
backward → system backward → tools backward (reverse cache order) for
the last cache_control marker, truncates, attaches a sentinel user
message when needed. Second probe fires in parallel; null/missing
leaves the field absent.
- src/core/transform.ts + tracker.ts: new baselineCacheableTokens /
baseline_cacheable_tokens fields, emitted only when > 0.
- src/dashboard.ts: per-event cache-aware math in update() and
replay(); Totals renamed to baselineInputWeighted; /proxy-stats
payload field is `baseline_input_weighted`.
- src/sessions.ts: per-session tokensSavedEst uses the same formula so
session and global rollups agree.
Tests: 2 new in proxy-usage covering (a) body with cache_control →
two probes fire with different bodies and both numbers land on info,
(b) cacheable-prefix probe failure doesn't poison the full probe.
260→262 tests, all green; typecheck and build clean.
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teamchong
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424f84172a | docs(sessions): fix stale field docs that still claimed estimation | ||
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teamchong
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f8902732bb |
feat(dashboard): real saved% from count_tokens, rip α-regression dead code
The headline saved%/saved$ numbers are now MEASURED, not estimated:
baseline = sum of /v1/messages/count_tokens(originalBody).input_tokens
actual = sum of (input + cache_create×1.25 + cache_read×0.10)
saved = baseline − actual
Output is excluded from both sides — it's identical with or without
compression (same prompt → same response), so it cancels in the
numerator and would only drag the percentage toward zero. The proxy
now makes one parallel side call to /v1/messages/count_tokens (free,
no billing) before forwarding /v1/messages, and the result lands on
TransformInfo.baselineTokens → TrackEvent.baseline_tokens → the
DashboardState rollup.
Removed (~280 lines of dead code):
- FALLBACK_ALPHA, FALLBACK_ALPHA_LOW, FALLBACK_ALPHA_HIGH constants
- estImageTokens(), baselineCost(), effectiveCost() helpers
- FitSample interface + FIT_SAMPLE_CAP + fitSamples ring buffer
- DashboardState.fitCosts() (~218 lines of OLS regression)
- Three-mode ladder (joint / constrained / stale) and all UI for it
- saved_pct_low/high, saved_effective_tokens_low/high range fields
- renderSavingsMath() range/regime branches
- m_pct_regime DOM node + its color/text wiring
- cost_fit payload field + all frontend consumers
/proxy-stats payload is now: requests, compressed_requests,
baseline_input_tokens, actual_input_weighted, saved_input_tokens,
saved_pct, saved_usd, pricing_assumptions, uptime_sec,
compression_enabled. Nothing else.
The recent-requests table now shows baseline / actual / saved per
row (input-side, matching the cards) instead of the old img-tok
estimate + effective_actual (which mixed output × 5 in inconsistently).
Sessions panel: per-session tokensSavedEst now uses the same real
baseline−actual formula. Events without both a count_tokens probe
AND an upstream usage block don't contribute to the rollup — no
synthetic 4-char/tok fallback.
Tests:
- dashboard-fit.test.ts: deleted (fitCosts is gone)
- proxy-usage.test.ts: inverted the privacy regression — count_tokens
is now explicitly expected as the one whitelisted side path; added
baselineTokens-attachment and count_tokens-failure-survives tests
- sessions.test.ts: rewrote the two savings tests against the new
baseline_tokens + usage formula
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teamchong
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1d46b72221 |
rip(proxy): remove count_tokens probe path — leaks original text
Sending the pre-compression body to /v1/messages/count_tokens means
Anthropic sees the original text, which is exactly what pixelpipe is
built to prevent. Probe results were 'free' in dollars but not in
privacy; the whole point of imaging the slab is that Anthropic does
NOT receive the slab text.
Removed:
- countTokensUpstream + buildCountTokensBody in src/core/proxy.ts
- measurePromise wiring + finalize await
- baselineTokensMeasured / actualTokensMeasured on TransformInfo
- baseline_tokens_measured / actual_tokens_measured on TrackEvent
- measuredEvents / effectiveCostActualMeasured / *Baseline*
fields on DashboardState
- measured_events / saved_pct_measured / effective_cost_*_measured
/ saved_effective_tokens_measured on /proxy-stats payload
- HTML headline branch + 'show calculation' rows for measured path
- 2 dashboard-fit tests asserting the measurement-path behavior
Added regression test: proxy must NOT hit any upstream path other than
/v1/messages.
Real-savings path now: self-derive α from billed usage + own char
walker. Coming next.
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teamchong
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e5bad22cd5 |
fix(proxy): strip non-count_tokens fields before probing
count_tokens accepts only model/messages/system/tools/tool_choice/thinking/ mcp_servers. Forwarding the verbatim /v1/messages body included stream, max_tokens, temperature, metadata etc, which the endpoint rejected with 400. Probe returned null silently → measured_events stuck at 0. Strip to the accepted fields before posting. Now both probes succeed, the dashboard headline can use saved_pct_measured = (Σ baseline − Σ actual) / Σ baseline — exact, no regression, no priors. Diagnostic logging kept on the probe path: failures surface in stderr instead of disappearing. |
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teamchong
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00b7c80e84 |
feat(dashboard): runtime passthrough toggle + consistent range UI
Three changes addressing operator feedback after seeing the math panels:
1. Passthrough kill switch (the main ask). When upstream is unhealthy
or the proxy is misbehaving, the operator needs to disable
compression instantly without restart. Adds:
- DashboardState.compressionEnabled (in-memory, defaults true)
- POST /api/compression {enabled: bool}
- compression_enabled field on /proxy-stats
- Red banner "PASSTHROUGH MODE" + toggle button at top of dashboard
- node.ts transform fn returns {compress:false} when off, so the
proxy forwards /v1/messages unchanged to upstream
- In-memory only — restart resets to enabled. No CLI flag, no env
var. Runtime control via dashboard.
2. $ saved card now shows a range when one is available, mirroring
the % card. Previously the % was "0.3%–11.7%" but $ was just
"$0.2569" — visually inconsistent. New behavior: compute usdLo/usdHi
from saved_effective_tokens_{low,high} × input_per_mtok; show range
when spread ≥ 1¢, point otherwise. Both cards now feel like the
same headline.
3. Math-panel jargon replaced with plain English. The previous text
said "p10/p90 of per-sample α across fit ring" — incomprehensible
without statistics background. Now reads "low/high bounds from
recent traffic's chars-per-token spread" on both savings-tokens and
reduction-% panels.
Tests: 277/277. Typecheck + build clean.
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teamchong
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c3506e3a2c |
fix(transform): flip compressHistory default to false
Round-3 measurement on 2026-05-19 with 128-turn history showed the feature loses money: 21K chars of text replaced with 140K tokens of imagery, net -250% savings per request on this traffic shape. The MARGINAL warning has been in the code comments since the feature shipped - it was opt-in via --history / COMPRESS_HISTORY=1 originally for exactly this reason. The recent flag-removal commit flipped it on as default without re-verifying the savings claim against current traffic. The math in baselineCost() correctly reports negative savings when imgTokensEst > txtReplaced, so the dashboard was honest about the loss - the bug is shipping the feature on by default before measuring a positive delta on representative traffic. Re-enable per-deployment via env var when measurement confirms a positive saved_pct on the specific shape. |
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teamchong
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328ea7e833 |
feat(dashboard): inline math panels under every savings card
Each headline card (tokens saved / $ saved / reduction %) gains a
collapsible "show calculation" panel that lays out the exact formula
plus the live numbers feeding it. Every digit on the headline can be
derived from what the panel shows — no estimation hidden behind a
black box.
Panels:
- tokens saved: actual_paid, baseline_est, saved formula
weights: input ×1.0, cc ×1.25, cr ×0.10, output ×5.0
- $ saved: formula = saved_tokens × input_per_mtok / 1e6,
exposes pricing_assumptions (rate ratios + source URL)
- reduction %:
- measured path (when count_tokens succeeded on ≥1 event):
baseline_tokens, actual_tokens, saved, saved_pct, n samples
labeled "ground truth, no estimation"
- estimated path (no measured events yet):
α-regression baseline, actual, saved, range from p10/p90
labeled "estimated · α-regression from cold-miss events"
- image-cost formula reference: tokens ≈ width × height / 750
Implementation:
- Native <details> elements, no JS framework. summary is a small
blue toggle that opens an inline formula block styled like a code
fence (dark background, monospaced).
- renderSavingsMath(s) is called once per /proxy-stats tick from the
existing fast-tick path. fmtRow builds key-value-note lines so the
three panels share a layout.
- pricing_assumptions block (input_per_mtok, output_multiplier,
cache_*_multiplier, source URL) already exists on /proxy-stats from
the earlier pricing-correction commit; this surfaces it inline.
No new endpoints, no new fields. The transparency comes entirely from
re-using existing /proxy-stats data and laying it out plainly.
Tests: 277/277. Typecheck + build clean.
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teamchong
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a66a558b55 |
refactor: remove all CLI flags and behavior env vars — single codepath
The proxy used to expose ~20 behavior toggles (--no-compress, --no-tools, --no-schemas, --no-reminders, --no-tool-results, --history, --no-history, --history-keep-tail N, --history-min-prefix N, --min-chars N, --min-reminder-chars N, --min-tool-result-chars N, --cols N, --multi-col N, --no-track, --events-file PATH, --port N, --upstream URL) plus matching env vars. Each one was a dead branch in the common case and a configuration knob nobody had a principled reason to pick a value for. Replaced with: exactly one way to run the proxy. Every compression mode on, every tuning parameter at its measured-best value, history compression always active (was opt-in dead code). The only adjustable surface is deployment concerns — where to listen, what to forward, where to log — env-var only: PORT default 47821 ANTHROPIC_UPSTREAM default https://api.anthropic.com PIXELPIPE_LOG default ~/.pixelpipe/events.jsonl CLI accepts only --help and --version. Anything else exits with non-zero and a one-line error. Notable behavior change: - DEFAULTS.compressHistory flipped false → true. Variant-C history- image compression now runs on every request (was opt-in via --history / COMPRESS_HISTORY=1). The static-slab cache_control placement is on the system image, not on the history-replacement chain, so the published cache-topology risk does not apply. Touched: - src/node.ts: CliOpts → RuntimeConfig (3 fields). parseCli is now ~25 lines. printHelp reduced to env-var-only doc. - src/core/transform.ts: DEFAULTS.compressHistory = true. Comment updated. - scripts/restart.sh: drops PROXY_ARGS array entirely. Port read from PORT= env var. Unknown args rejected. - tests/restart.test.sh: replaces flag-passthrough test with a reject-unknown-args test. 4/4 pass. - tests/history.test.ts: renames the "compressHistory:false (default)" test to reflect the new always-on default; asserts the input-not- mutated invariant remains. - README.md: configuration table reduced to 3 env vars; restart examples drop CLI flag passthrough. Tests: 277/277. Typecheck + build clean. Restart script tests: 4/4. |
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teamchong
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c4aa5af342 |
refactor(proxy): remove measureSavings flag — count_tokens always runs
The measurement code was previously gated behind a measureSavings flag (--measure-savings CLI, PIXELPIPE_MEASURE_SAVINGS env var, optional ProxyConfig field). That's a knob nobody asked for and a second codepath whose only purpose is to leave the dashboard reporting estimates instead of ground truth. The flag is wrong for this codebase: - Single codepath is the convention. The proxy either measures or doesn't — there's no useful "sometimes" mode. - count_tokens is free, runs in parallel with the main upstream forward, and doesn't add user-visible latency. - An opt-in default means the headline dashboard number stays as an estimate forever in 99% of deployments — defeats the whole feature. Removed: - ProxyConfig.measureSavings field - CliOpts.measureSavings field - --no-measure-savings CLI handler - PIXELPIPE_MEASURE_SAVINGS env var - The if (config.measureSavings) wrapper in proxy.ts - Help-text entry - Stale comment references in tracker.ts, transform.ts, dashboard.ts The proxy now unconditionally fires count_tokens on both bodies for every /v1/messages request. Failure is silent — when count_tokens returns null the event still emits without the measured fields and the dashboard falls back to the regression estimate per existing fallback logic. Tests: 277/277. Typecheck + build clean. No behavioral test changes; the existing measurement-path test exercises the synthetic event shape directly, not the flag. |
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teamchong
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6f0d1a9914 |
feat(proxy): ground-truth saved_pct via count_tokens on both bodies
Replace estimation with measurement. Anthropic's /v1/messages/count_tokens
returns the exact tokenizer output for any request body, free of charge.
Calling it on the pre-transform body and the post-transform body gives
the EXACT delta in input tokens, with no α/β regression, no fallback
constants, no uncertainty band needed.
Opt-in (default off, since it adds two parallel HTTP roundtrips per
/v1/messages — count_tokens itself is free but the latency is real):
CLI flag: --measure-savings
Env var: PIXELPIPE_MEASURE_SAVINGS=1
When enabled the proxy fires both count_tokens calls in parallel with
the main upstream forward (no critical-path latency hit) and the event
is held for emit until both probes complete. Failures are silent — the
event still emits without the measured fields and the dashboard falls
back to the estimate.
Per-event new fields (events.jsonl):
baseline_tokens_measured exact pre-transform input tokens
actual_tokens_measured exact post-transform input tokens
Dashboard:
/proxy-stats gains: measured_events, effective_cost_actual_measured,
effective_cost_baseline_measured, saved_effective_tokens_measured,
saved_pct_measured. All null when no measured events exist; non-null
once ≥1 lands.
HTML headline switches to the measured number whenever measured_events
≥ 1. Subtitle reads "measured · count_tokens on N requests" to make
the source explicit. Falls back to the estimated range otherwise.
Measurement math:
delta_tokens = baseline_measured - actual_measured
bill_rate = (cc/total)·1.25 + (cr/total)·0.10 [same cache mix
as the actual call]
baseline_eff = actual_eff + delta_tokens · bill_rate
saved_pct_measured = (baseline_eff - actual_eff) / baseline_eff × 100
No α. No β. No FALLBACK_*. The numerator (delta_tokens) is the exact
output of Anthropic's tokenizer on both bodies; the multiplier is the
billed cache mix that already happened.
Tests: 275 → 277 (+2). Ground-truth path: 3 events with known token
deltas yield the expected saved_pct_measured. Fallback path: when no
event carries measurement, all saved_*_measured fields are null.
Typecheck + build clean.
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teamchong
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5b5f48919d |
fix(dashboard): correct pricing/image constants from docs.anthropic.com
Audit against published Anthropic docs (pricing + vision pages,
verified 2026-05-19 via WebFetch) found three constants in this file
that were either wrong or hand-picked without citation. Replace them
with documented values and add a PROVENANCE block so the lineage is
auditable.
Corrections:
1. saved_usd headline rate: $15/Mtok → $5/Mtok.
Opus 4.7 base input rate per docs is $5/Mtok, not $15. The old
value was Opus 3 pricing repurposed by the field name "_opus47".
The headline dollar number was therefore overstated by 3× on any
Opus 4.x deployment. Renamed field to saved_usd_estimated and
exposed pricing_assumptions{input_per_mtok, multipliers, source}
on /proxy-stats so the operator can verify what we multiplied by.
2. Per-image token cost: drop fixed OPUS_IMAGE_TOKEN_COST=2500 in
favor of the published formula tokens ≈ width × height / 750
(docs-vision). estImageTokens now prefers (in order): live β fit
→ published 1/750 → FALLBACK_IMAGE_TOKEN_COST (=1690, computed
from the formula at our default 808×1568 render). The old 2,500
constant traced to an in-house measurement that didn't reconcile
with the docs; pending a fresh per-renderer-config measurement
under post-walker-fix code.
3. FALLBACK_ALPHA point estimate: 0.25 → 0.33. Opus 4.7's tokenizer
note in [docs-pricing] explicitly states ~35% denser than older
models for the same text. CHARS_PER_TOKEN=4 (the older English
average) is therefore biased for Opus 4.7 traffic; 3 chars/tok
matches the documented behavior. The low/high brackets (0.15 /
0.50) span both tokenizer regimes and are left alone.
Added:
- PROVENANCE comment block at the top of the pricing/image-cost
section citing the three doc URLs and the verification date, with
each downstream constant footnoting back to one of the labels.
- pricing_assumptions object in /proxy-stats payload exposing every
multiplier and the source URL.
- Test pinning the pricing_assumptions shape and the
saved_usd_estimated = saved_tokens × input_per_mtok / 1e6 identity.
What this does NOT yet correct:
- Live α and per-renderer β still require fresh measurement post-
walker-fix. The fallback brackets keep saved_pct conservative
until the regression converges.
- 1-hour cache writes (2× input) are exposed in pricing_assumptions
but not yet distinguished from 5-minute writes in the cost math —
needs an upstream signal we don't currently capture per-event.
Tests: 274 → 275 (+1). Typecheck + build clean.
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teamchong
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d02a0f9baf |
feat(dashboard): fold output tokens into saved_pct (full-bill framing)
effectiveCost() previously summed only input + cache_create·1.25 + cache_read·0.10, leaving output tokens out of the cost total. The headline saved_pct was therefore "% saved on the input-side bill" rather than "% saved on the full upstream bill." Output is small in absolute terms on typical Claude Code traffic (≈0.4% of cost in the sample events.jsonl), but the framing is what matters. Changes: - effectiveCost gains an outputTokens parameter and sums output × OUTPUT_TOKEN_RATE (=5.0, the Opus/Sonnet output:input rate ratio). - Totals fields renamed effectiveInput* → effectiveCost* to match the new full-bill semantics. Same on the JSON wire: effective_input_* → effective_cost_*. - update() now also passes the event's output_tokens into effectiveCost so both actual and baseline grow consistently. - replay() effective_actual computation includes output_tokens too, so historical rows align with the live formula. - Headline subtitles updated to "share of total bill saved" and "effective tokens (full bill)" so the unit is self-documenting. Math invariant: output is identical in actual and baseline (the model produces the same response regardless of prompt compression), so it cancels in the numerator saved = baseline - actual but inflates the denominator. saved_pct therefore moves SMALLER and more conservative when output is non-trivial — honest whole-bill terms. New test pins the invariant: two identical input-side runs with 100× different output_tokens give the SAME saved_effective_tokens but strictly different saved_pct, with the higher-output run lower. Tests: 273 → 274 (+1). Typecheck + build clean. |
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teamchong
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e27c19c2a3 |
feat(transform): live-α charsPerToken closes not_profitable max-savings leak
The break-even gate (isCompressionProfitable) used a hard-coded CHARS_PER_TOKEN=4 (Anthropic's English avg). Live Claude Code traffic has α≈0.5-0.9 (1.1-2 chars/tok) — JSON-dense tool docs, structured CLAUDE.md slabs, etc. Off-by ~3.5× on the text side at α=0.88. Production trace (events.jsonl, 2026-05-19): 200+ requests with system slabs 113K-170K chars hit reason="not_profitable" because the gate's textTokensEq = len/4 was a fraction of the row-aware image-token cost. Example event: slab=169_632 chars, cache_create_tokens=148_891. Gate's textEq=42K rejected vs imgCost=127K. With live α (1.14 ch/tok), textEq=149K → ACCEPT. We were leaving real cache_create money on the table on every one of those calls. - TransformOptions gains charsPerToken?: number. Default 4 (back-compat). - isCompressionProfitable() takes charsPerToken as a 5th optional param; defensive clamp on ≤0 / NaN / Infinity falls back to CHARS_PER_TOKEN. - All 4 internal gate call sites (static slab + reminder + tool_result string + tool_result array) thread o.charsPerToken through. - ProxyConfig.transform now also accepts a function: () => TransformOptions. Resolved per-request inside createProxy so the host can inject dynamic values. Static-object form unchanged for Workers / tests. - node.ts wraps the static transform options in a closure that asks dashboardState.fitCosts() each request and passes the live chars_per_token. Fit-null falls through to the baked-in default — no chicken-and-egg deadlock since normal-sized slabs still feed the fit ring even before the huge-slab cases get unblocked. - 4 new gate tests: stale-default rejects the 170K newline-heavy slab; live α=1.14 flips the same slab to profitable; defensive clamp on bogus charsPerToken; end-to-end transformRequest passes through. Tests: 269 → 273 (+4). Typecheck + build clean. |
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teamchong
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9c860f02dd |
feat(dashboard): sessions bulk select + delete (Gmail/GitHub pattern)
The sessions table previously only supported per-row deletion via the "del" button — no way to clear many at once. Add an industry-standard multi-select pattern. Pattern follows Gmail / GitHub / Linear / Vercel: - Leftmost cell on each row is a checkbox; data-id binds to session id. - Header checkbox is tri-state (empty / indeterminate / all-on-page) driven by a single source of truth (selectedSessionIds: Set<string>). - Shift-click on a row checkbox does range-select from the last-clicked anchor to the current row, applying the new checked state to every row in between (macOS Finder / Gmail convention). - Contextual action bar slides in above the table when ≥1 row is selected, showing "N selected · Delete selected · Clear (Esc)". - Confirm modal shows count + first 3 session id prefixes + "and N more" for sanity-check before destructive action. - Esc key clears the selection (no-op when an input is focused). - Selection is keyed on session id and reapplied after each diff render — innerHTML rewrites no longer clobber checked state. - Vanished sessions auto-drop from selection. Backend: - PruneOptions gains sessionIds?: string[] alongside the existing single sessionId. Unknown ids are silently skipped (race-safe with concurrent prunes). Composes with sessionId if both are set. - handlePrune plumbs sessionIds through; the bulk-delete action calls /api/sessions/prune once with all ids. - 3 new selectSessionsToRemove tests: bulk select, unknown-id skip, sessionId+sessionIds composition. Tests: 266 → 269 (+3). Typecheck + build clean. |
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teamchong
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0a25aeb51d |
feat(dashboard): honest saved_pct uncertainty band (saved_pct_low..saved_pct_high)
The headline used to publish a precise saved_pct (e.g. "68.2%") even
when α was thin / fallback. Switch to a range whenever uncertainty is
wide enough to matter — point estimate only when the spread is tight.
- fitCosts() returns alpha_low / alpha_high (and chars_per_token bounds)
from p10/p90 of per-sample residual α = (tokens - β·pixels) / chars
across the fit-sample ring. For n≤3 uses min/max; for larger n uses
10th/90th percentile. Order-clamped against the central point so a
noisy sample can't put low > point or high < point.
- baselineCost() gains an optional alphaOverride knob that varies ONLY
the chars-per-token side while keeping the image-cost regime stable
(β·pixels when fit is present, 2500/img fallback otherwise). Without
this knob, an earlier draft mixed regimes and produced
saved_pct_low > saved_pct — silently incoherent.
- Totals tracks three parallel baselines: effectiveInputBaselineEst
(point), …Low, …High. Every event updates all three.
- /proxy-stats exposes saved_pct, saved_pct_low, saved_pct_high plus
the matching effective_input_baseline_est_{low,high} and
saved_effective_tokens_{low,high}. Bounds clamped ≥ 0.
- HTML headline collapses to point estimate when (high − low) < 5 pp;
otherwise renders "lo–hi%" as the headline with point as subtitle.
- When fit is null (n<3), wide fallback brackets (0.15 / 0.25 / 0.50)
produce a deliberately wide range so the headline shows a calibrating
state instead of a fake-precise point estimate.
- 5 new tests: alpha_low ≤ alpha ≤ alpha_high invariant, chars/tok
bound inversion, serveStats bound monotonicity, null-fit range shape,
and warmup-baseline ordering.
Tests: 261 → 266 (+5). Typecheck + build clean.
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teamchong
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17b77c7492 |
fix(transform): count tools[], tool_use, thinking blocks in outgoingTextChars
The walker was missing three big text-bearing paths the upstream tokenizer sees: top-level `tools[]` (name + description + JSON schema), `tool_use` blocks (name + serialized input), and `thinking` blocks. Under-counting these inflates α in `tokens ≈ α·textChars + β·pixels`, which biases the dashboard's `saved_pct` HIGH — the honesty cost HANDOFF item #1 called out. - Walker now sums: system + tools[].{name,description,input_schema} + per-block text/tool_use.input/tool_result.{tool_use_id,content}/ thinking. JSON.stringify via safeStringifyLen() for object fields so the count matches what the API actually serializes. - Lift the walker call out of the compression-success path: also run it on the below_min_chars and not_profitable early returns. Without this, α was sampled only from "big enough to compress" requests. - New `outgoingTextChars walker (denominator honesty)` describe block in render.test.ts: 7 tests covering baseline, tools[], tool_use, tool_result (string + array forms with image skip), thinking, unknown-block skipping, and a JSON.stringify(req).length upper bound asserting walker ≥ 50% of envelope on a content-dense request. - Confirms walker stays strictly below the JSON envelope (structural keys/braces still excluded — that's intentional). Tests: 254 → 261 (+7). Typecheck + build clean. |
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teamchong
|
269ae4503a |
dashboard: drop constrained CV gate to 0.1% + surface text_cv on badge
Live diagnosis: real steady-state single-session traffic has 1-2% text
CV turn-to-turn (verified 2026-05-19: six consecutive turns at 132,738
/ 133,021 / 133,610 / 134,105 / 134,718 / 138,097 chars = 1.33% CV).
The previous 2% gate I'd set was still too tight — the constrained fit
never activated, dashboard stayed on stale-constants regime indefinitely.
The CV gate was over-protective. With β pinned, α = Σ(r·x)/Σ(x²) is
mathematically well-defined and numerically stable at any cvX > 0. The
gate only matters for splitting two collinear parameters (joint mode).
For constrained mode I'm replacing the gate with a confidence display:
- MIN_CV_CONSTRAINED = 0.001 (0.1% — purely defensive against
byte-identical sample collapse)
- text_cv + pixels_cv added to cost_fit JSON response
- badge surfaces 'text CV X.X%' so operator sees confidence directly
- constrained-mode badge color tracks CV:
blue = robust (CV ≥ 5%)
amber = thin but measured (1% ≤ CV < 5%)
gray = mean-ratio estimator (CV < 1%)
This is the right shape: don't gate, show the number. The operator can
judge whether '38% saved at text CV 1.3%' is trustworthy enough.
Tests:
+ new: 6-sample 1.33% CV fixture activates constrained mode + reports
cv fields
+ replaced: 'below 2% floor rejects' → 'byte-identical (cv=0) rejects'
unchanged: joint mode + collinear-pixels constrained mode
|
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teamchong
|
91c969b593 |
dashboard: split CV threshold — 5% joint / 2% constrained
Live-traffic diagnosis: typical single-session warm-cache load has the same cached image across turns (pixel CV = 0%) AND text variance of 3-4% (verified 2026-05-19: 117k/127k/128k chars across three turns = 3.84% CV). Both columns failed the original 5%-everywhere gate, so the constrained fallback I just shipped never actually activated — the dashboard fell straight through to wandering stale constants. The 5% gate exists to stop joint OLS from splitting two indistinguishable parameters. In constrained mode β is pinned (no split to make), so we're fitting one parameter through the origin — 1-D OLS is numerically stable at much lower variance. 2% is conservative; even 1% would converge. New thresholds: MIN_CV_JOINT = 0.05 (unchanged — both columns must vary) MIN_CV_CONSTRAINED = 0.02 (NEW — text only, β-pinned through origin) Real-world impact: live single-session traffic now activates constrained mode after 3 compressed turns instead of waiting for cross-session variance that may never arrive. Dashboard label flips from amber 'stale constants' to blue 'constrained · α-only' — operator sees a measured α within ~30 seconds of starting a fresh proxy. Tests: + new: live-traffic-shape sample activates constrained mode (3.84% CV) + new: below-2% floor still rejects (no garbage 1-D fits) unchanged: 2-D collinear cases still null, joint-fit at high CV still returns mode='joint' |
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|
teamchong
|
9d3984fd03 |
render: multicol gutter divider (light-gray boundary cue for OCR)
Paint a 1-pixel-wide mid-gray (191/255) vertical line in the center of
each gutter at multicol >= 2. Same 'visible whitespace' principle as the
U+2192 tab arrow — surfaces structure that pure whitespace alone leaves
ambiguous, at near-zero pixel-token cost (DEFLATE collapses identical
mid-gray runs to ~5 bytes per gutter).
Why now: the user noted gutters relied on whitespace alone, which is
exactly the OCR-reordering risk HANDOFF flagged for multi-col 2 (lines
322-326). An explicit boundary cue lets us push wider multicol or wider
cols in future without spooking the vision encoder into reading
left-to-right across columns.
Tests:
- byte-determinism (existing test still passes)
- inflate IDAT + assert mid-gray pixels at expected divider X
- numCols=1 path stays byte-identical to renderTextToPngs (deterministic
cache_control story for single-col deployments)
Cost: ink=64 pre-invert → 191 post-invert. Doesn't compete with glyph
ink (which lands at 0). At β=0.001776, the divider's ~1568 pixels cost
~3 tokens total per multi-col image. Trivial vs the OCR-clarity win.
|
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teamchong
|
3893fa6726 |
dashboard: constrained-fit fallback (β=1/750) + regime label on HTML
When the live OLS can't identify β separately (pixels column collinear because a single cached image dominates the 50-sample ring), fall back to α-only fit with β pinned to Anthropic's published rate. Returns mode='joint' | 'constrained' so the HTML can tell the operator which regime the headline saved_pct came from. Three-state badge under the reduction card: - green 'empirical · joint OLS (n≥10)' = both rates measured, confident - amber 'empirical · joint OLS (n<10, tentative)' = both measured, thin - blue 'constrained · α-only (β pinned 1/750)' = α measured, β=Anthropic - amber 'stale constants (no fit yet)' = pre-fit, treat skeptically Closes the 'wandering ±15pp until the fit fires' gap from HANDOFF: even under single-session traffic the dashboard now shows a measured α rather than oscillating between joint-OLS-degenerate and stale-constants. |
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teamchong
|
36ce17ebb6 |
dashboard: collinearity guard — refuse to activate fit when α/β unidentifiable
# The user-visible bug
Showed wandering saved_pct from oscillating OLS:
n=4: α=0.509, β=0.00387, saved_pct=20.1%
n=8: α=0.879, β=0.00104, saved_pct=25.0% (same session, 4 more samples)
# The root cause
A single Claude Code session sends warm hits with the SAME cached image
on every turn → `pixels` column has ZERO variance across samples. The
regression `tokens ≈ α·text + β·pixels` only identifies α and β
SEPARATELY when both columns vary. With pixels constant the model
degenerates to `tokens ≈ α·text + c` where c = β·p̄ — OLS distributes
the per-sample cost between α and β however the residual noise pushes,
and the split flips wildly as samples accumulate.
The det != 0 numerical check missed this because text has tiny non-zero
variance, so the matrix isn't EXACTLY singular — just near-singular,
which is enough for the headline to wander by ±15 pp.
# The fix
Add a coefficient-of-variation guard. Both columns must have CV (stdev
÷ mean) > 5% before fitCosts() returns non-null. Below that, the fit
is statistically meaningless and we fall back to the stale-constants
baseline. Better to show a stable known-wrong number than an unstable
unidentifiable one.
This is the OPPOSITE direction from the earlier 'cache_read===0' gate
relaxation (which was the right call — warm hits DO contribute to the
sample ring), but at a different layer:
- Gate at sample ingestion: liberal (any compressed request with
full usage triple)
- Gate at fit ACTIVATION: strict (require non-collinear samples)
# Known remaining biases (HANDOFF documents)
1. `outgoing_text_chars` undercounts — doesn't include `req.tools`
text. Measured slope α≈1.1 across collinear-pixels samples implies
~0.9 chars/token, vs Opus 4.7 reality 2.7-3.6. Probably ~half the
tokenized chars are missing from our walker.
2. Even with #1 fixed, β identification needs cross-session variance
(samples with different cached images). Either wait for cache TTL
expiry, drive multi-session traffic, or add a constrained-fit
fallback that pins β = 1/750 (Anthropic's published rate) and
solves α only.
# Tests
tests/dashboard-fit.test.ts: replaced the warm-hit-with-constant-pixels
test (which passed only because the old code had no CV guard) with two
new tests:
- returns null when pixels column is constant (single-session case)
- returns null when text_chars is constant (mirror case)
- activates the fit when both columns vary > 5% (cross-session-style
samples reconstruct α≈0.286, β≈1.5e-3 to within ~10%)
248 tests pass (up from 246).
# Milestone status
The dashboard is now HONEST (refuses to claim numbers it can't
measure) but NOT yet CALIBRATED (still on stale constants until cross-
session samples land). HANDOFF.md captures the path to calibration.
|
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teamchong
|
f14a159530 |
dashboard: drop the bogus 'cache_read===0' fit-sample gate
The earlier gate (`cache_read === 0 && cache_create > 1000`) was wrong.
Anthropic's tokenizer is deterministic on the request bytes — cache state
changes BILLING (cache_read is discounted), not token count. The total
tokenization of the request body is always:
total_tokens = input + cache_create + cache_read
…regardless of how it was split across cached/uncached portions. So warm
hits carry the same body-token information as cold misses; the regression
`tokens ≈ α·text_chars + β·pixels` is solvable from either.
The old gate locked the fit out of all normal traffic: warm hits ARE the
steady state once a Claude Code session has run a few turns. The user
correctly noticed that cost_fit stayed null forever even with the proxy
processing real requests, because every request after the first hits the
prompt cache.
# The fix
- Remove the `cache_read === 0` requirement.
- LHS becomes `input + cache_create + cache_read` (was `input + cache_create`).
- Keep the 1000-token floor (filters trivial no-system requests where
tokenizer overhead dominates).
- Rename `coldMisses` / `ColdMissSample` / `COLD_MISS_CAP` → `fitSamples`
/ `FitSample` / `FIT_SAMPLE_CAP` since the samples are no longer cold-
miss-gated.
# Collinearity guard already handles the single-session case
The OLS no-intercept solver uses det = sxx·syy − sxy². With pixels held
constant at p̄ (same cached image across a session's warm hits) but
text_chars varying turn-to-turn, det = p̄²·(n·Σx² − (Σx)²) which is
positive by Cauchy-Schwarz whenever text varies. So a single Claude Code
session can populate the fit on its own — no need to spawn N sessions.
# Tests
New tests/dashboard-fit.test.ts (5 cases) locks in:
- null below 3 samples
- warm cache hits DO seed the ring (the regression we're guarding)
- LHS = input + cache_create + cache_read (cold vs warm with identical
body lands on the same regression line)
- 1000-token floor still filters trivial no-system traffic
- compressed=false passthrough requests don't contaminate the fit
246 tests pass (up from 241), typecheck + build clean.
|
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|
teamchong
|
937f0f8817 |
prune: drop dead 'placement' + 'compressSystem' knobs (system-field branch was API-rejected)
The `placement === 'system'` branch attached image blocks to the `system`
field, which Anthropic 400s with `system.N.type: Input should be 'text'`.
The existing CLI help text already warned about this. No tests exercised
the dead branch (grep for `placement.*'system'` finds zero call sites).
`compressSystem` was only consulted inside that same dead branch, so it
went out with it. The other granular `compress{Tools,Schemas,Reminders,
ToolResults}` flags + the `compress` master switch stay — they're useful
debugging toggles with active call sites.
Touched:
- transform.ts: drop both fields from TransformOptions + DEFAULTS;
collapse the if/else around system-rewriting into a bare block (no
re-indentation noise, no behavior change).
- node.ts: drop --placement CLI flag, PLACEMENT env, help text entries,
startup log column, and the TransformOptions wire-up.
- worker.ts: drop PLACEMENT from Env + transform options.
- render.test.ts: refresh three comments that referenced the now-gone
"default placement is 'user'" language; the test bodies were already
correct and didn't reference the removed knobs.
20-line net reduction, 241 tests pass, typecheck + build clean.
|
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|
teamchong
|
a52423870b |
dashboard: wire empirical cost fit into headline savings math + handoff
`DashboardState.fitCosts()` runs OLS over a rolling 50-event ring of
cold-miss (image_pixels, outgoing_text_chars, cache_create_tokens)
samples. `baselineCost()` and `estImageTokens()` consult the fit on
every event:
- `cost_fit != null` (N ≥ 3 samples) → headline saved_pct switches to
the live empirical rates: txtReplaced = compressedChars × α,
imgTokens = imagePixels × β.
- `cost_fit == null` → falls back to the stale constants
(OPUS_IMAGE_TOKEN_COST = 2500, CHARS_PER_TOKEN = 4) — same behavior
as before, so nothing breaks while data accumulates.
# Why a rolling ring, not seeded from history
Old events may carry the new instrumented fields but come from a
different renderer config (cell size, multiCol, atlas profile) or a
different model (Opus 4.6 vs 4.7 tokenizer). Mixing them in gives a
misleading α/β that lags reality. Each restart starts the fit empty
and refills from live traffic, so flipping `multiCol`, swapping
fonts, or upgrading the model auto-flushes stale samples.
# Endpoint
`/proxy-stats` JSON payload now carries:
"cost_fit": {
"alpha": 0.3, "beta": 0.0053,
"chars_per_token": 3.3, "pixels_per_token": 189,
"single_col_tokens_per_img": 4180,
"multicol2_tokens_per_img": 8500,
"n": 12
}
null until ≥3 cold-miss samples land. Guards against degenerate fits
(collinear data, negative rates) by returning null rather than feeding
the dashboard noise.
# Math
Solves `tokens ≈ α · text_chars + β · pixels` via 2×2 normal
equations on the centered design matrix. Rounds α to 4 sig figs, keeps
β at 6 sig figs (β is tiny ~5e-3 so it needs the resolution).
# Open
Once N stabilizes at ~10+, re-grade the hardcoded
`OPUS_IMAGE_TOKEN_COST` and `CHARS_PER_TOKEN` constants to match the
empirical numbers. That just makes the fall-back path agree with
reality, doesn't change live behavior. HANDOFF.md captures the
verification recipe and priority queue for the next session.
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teamchong
|
f1688e9f46 |
transform+render: R2 multi-col default-on + per-request pixel/char instrumentation
Two pieces of work landing together because they're interleaved in transform.ts and need to ship at the same time for the dashboard fit-wiring in the next commit to work. # R2 multi-column rendering (default `multiCol=2`) Single-col packing wastes ~68% of Anthropic's 1568×1568 image budget on real Claude Code tool docs (~38 chars/row). The row-aware break- even gate correctly rejects compression on those slabs — proxy ends up doing nothing on the heaviest requests. Multi-col packs N text columns side-by-side per image so each image covers `N×LINES_PER_IMAGE` wrapped lines, dropping image count by ~N and crossing break-even. - render.ts: new `renderTextToPngsMultiCol(text, cols, numCols)` with column-major layout (col 0 fills top-to-bottom, then col 1, …). Plus `multiColWidth` / `maxFittingCols` helpers. CLI auto-clamps numCols so the canvas can never exceed the 1568 px width cap. - transform.ts: `multiCol` option threaded through; gate, image-count estimator, paging budget, and all render paths take `numCols`. Intro text now describes column reading order when numCols>1 so the OCR pass doesn't read row-wise across columns. - Host wiring: node.ts (--multi-col / MULTI_COL=N, default 2), worker.ts (MULTI_COL env, default 2). Startup log shows multi_col=N. - numCols=1 stays a byte-identical passthrough to renderTextToPngs so flipping back can't regress the cache_control hit rate. # Empirical-cost instrumentation The dashboard's `OPUS_IMAGE_TOKEN_COST = 2500` and `CHARS_PER_TOKEN = 4` are stale pre-Opus-4.7 constants. Fact-checked: 4.7 changed the TEXT tokenizer only (~1.20× inflation on English, ~1.36× on TypeScript); image cost is unchanged for same-size images. Direction of error in the dashboard headline: it UNDERSTATES text savings. Ditched the "guess from one cold-miss" approach in favor of real instrumentation that pins both axes at once: - TransformInfo.imagePixels — Σ width×height across every image this request (static slab + reminders + tool_results + history collapse). Threaded through textToImageBlocks, collapseHistory. - TransformInfo.outgoingTextChars — every char of TEXT remaining in the transformed outgoing body, computed in one walk before serialization (countOutgoingTextChars). - Tracker event schema picks up image_pixels + outgoing_text_chars. - history.ts: HistoryCollapseInfo.collapsedImagePixels accumulates. The regression `tokens ≈ α·outgoing_text_chars + β·image_pixels` over N cold-miss events solves for empirical chars/token (α) and pixels/token (β) under the live model — no assumed constants. # Tests - 8 new render tests covering the multi-col passthrough contract (numCols=1 byte-identical to renderTextToPngs), canvas dimensions, image-count halving, determinism, charsRendered sum, estimator parity, CLI clamp, and CJK wide-glyph wrap. - paging.test.ts "counts multiple tool_results" threshold loosened from >770k to >700k to cover both single-col and multi-col budgets at the same maxImagesPerToolResult cap. - All 241 tests pass, typecheck + build clean. |
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teamchong
|
aed76dbdc2 |
transform: compact JSON in tool docs (kills the sparse-fill crisis)
renderToolDoc pretty-printed every input_schema with 2-space indent,
putting each property on its own line. At cols=100 this wasted ~70% of
horizontal space — schemas rendered to many short rows instead of a few
dense ones.
Live measurement on 2026-05-19: 150 KB of pretty-printed tool docs in a
177 KB combined slab → 31 static-slab images per request at 40% fill.
With the new row-aware break-even gate (
|
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|
teamchong
|
f0176c1432 |
transform: row-aware break-even gate stops net-loss compressions
isCompressionProfitable previously estimated image count as
ceil(chars / charsPerImage), which assumes uniform full-width line-fill.
renderTextToPngs actually budgets by wrapped visual rows (141 per image),
so newline-heavy code/logs and short-line content render to many more
images than the chars-based estimate predicts.
Live impact: dashboard reported -69% reduction (net loss). 33 compressions
averaged 5494 chars/image (39% fill ratio) — gate under-counted cost by
~9× on sparse content and let net-losing compressions through.
Fix:
- isCompressionProfitable now accepts the full text string; uses
estimateImageCount (the same row-aware math renderTextToPngs uses).
- Adds an optional imageCountCap for paths that truncate before rendering
(tool_results). Cost bounded by cap; savings still measured against
the full pre-truncation length, so 500KB logs still profit.
- All 4 production call sites in transform.ts pass the string. The
tool_result sites also pass maxImagesPerToolResult as the cap.
- Number-arg form retained for back-compat with the existing
isCompressionProfitable(N) unit tests.
Tests:
- 3 new unit tests pin the row-aware regression: sparse content rejected,
dense content accepted, capped content (paging) accepted.
- 7 integration tests previously used 'claude.md\n'.repeat(5000) — sparse
fixtures the new gate correctly rejects. Updated to dense fixtures
('x'.repeat(40000) or single-line repeats without embedded newlines)
so they still exercise the cache_control / determinism / reminder /
tool_result code paths they're meant to.
|
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|
teamchong
|
8fbd53ea3e |
dashboard: fix bogus savings math + emit compressed_chars
The dashboard headline was showing 0% saved because the math was
apples-to-oranges:
- orig_chars = static slab + tool docs ONLY (~135 KB)
- image_count = ALL images including reminders + tool_results (~33)
- txtReplaced = 135k/4 = 33.7k tokens
- imgTokensEst = 33 × 2500 = 82.5k tokens
- extraText = max(0, 33.7k - 82.5k) = 0 ← clamped negative
- baseline == paid → 'saved 0%' headline despite real savings happening
Two fixes:
1. Track 'compressedChars' separately from 'origChars'. It accumulates
only when a block actually image-renders (passes the break-even gate
AND any per-block min thresholds). Includes the static slab + all
compressed reminders + all compressed tool_results.
2. Remove the Math.max(0,...) clamp in baselineCost(). Negative savings
surface honestly — they're the signal that small-block compressions
are cost-bleeding, which the break-even gate is supposed to prevent.
Wires:
- TransformInfo.compressedChars (new field, mandatory).
- All 4 image-render success paths accumulate (static slab + reminder
+ tool_result string branch + tool_result array branch).
- TrackEvent.compressed_chars (new optional field, emitted when > 0).
- dashboard.baselineCost() takes compressedChars now; clamp removed.
- sessions.aggregateSessions() also uses compressed_chars + honest math.
229/229 tests passing. Bundle stays at 496 KB gzipped.
Post-restart, the dashboard 'tokens saved' will show real numbers
including negatives. Empirically expect ~1-5% net positive in
steady-state cache-hit traffic.
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|
teamchong
|
4f5b10aaee |
host: wire Variant C history-image opts through node + worker CLI
Threads compressHistory / historyKeepTail / historyMinPrefix through CliOpts, env vars (COMPRESS_HISTORY, HISTORY_KEEP_TAIL, HISTORY_MIN_PREFIX), and CLI flags (--history, --no-history, --history-keep-tail N, --history-min-prefix N). Same wiring on Workers host. Startup log reports history=on/off. TrackEvent extended with 4 new fields (collapsed_turns, collapsed_chars, collapsed_images, history_reason) — emitted only when non-zero/defined. Defaults: compressHistory=false (opt-in given round-3 MARGINAL rating). 229/229 tests green, 496 KB gzipped. |
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|
teamchong
|
97fdee8421 |
history: Variant C closed-tool-sequence collapse + honest per-session savings
Two distinct improvements in one slice:
1. History-image compression (Variant C — opt-in, default OFF).
New src/core/history.ts module:
- findClosedPrefixBoundary(): walks tool_use_id openSet, returns largest
fully-closed prefix index. Mid-flight tool_use blocks bail the collapse.
- blocksToText(): linearises content blocks for the history image. Drops
thinking blocks (per Opus 4.7+ docs: only most-recent must be bit-perfect),
renders tool_use args + tool_result inner text, emits [image] placeholder
for nested images.
- collapseHistory(): orchestrates. Applies isCompressionProfitable() gate.
Returns a synthesized {role:'user', content:[text,image,text]} prepended
message + the elided turns dropped from messages[].
New TransformOptions: compressHistory (default false), historyKeepTail (4),
historyMinPrefix (10). Wired through src/node.ts + src/worker.ts as
COMPRESS_HISTORY / HISTORY_KEEP_TAIL / HISTORY_MIN_PREFIX env vars.
Cache_control: history-image carries NO cache_control on this first cut.
Static slab keeps its 1 breakpoint. Conservative — telemetry will reveal
whether the cache-miss rate on history images warrants the round-3
rebalance in a follow-up slice.
29 new tests in tests/history.test.ts: closed-prefix detection (parallel
tool calls, mid-flight, openSet straddling), block linearisation, full
collapse flow, isCompressionProfitable gate firing on small histories.
2. Per-session savings: honest formula (fixes task #63).
Previous src/sessions.ts computed saved = orig_chars - image_bytes — a
nonsense comparison of chars to PNG bytes, then clamped via Math.max(0,...).
Result: charsSaved/tokensSavedEst was 0 for every session including ones
with hundreds of MB of compressed traffic.
New formula mirrors src/dashboard.ts:
textTokens = orig_chars / 4
imageTokens = image_count × 2500
tokensSaved = textTokens − imageTokens (CAN be negative)
Negatives are NOT clamped — they surface the cost-bleed on small-block
compressions that the per-block break-even check is supposed to prevent.
2 new tests: positive-net case, all-negative case (must report negative).
229/229 tests passing. Bundle ~500 KB gzipped.
|
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|
teamchong
|
04b1526bd5 |
transform: large-tool_result paging + adaptive break-even derivation
Two related improvements:
1. Per-tool_result paging / truncation. When a single tool_result would
render to more than maxImagesPerToolResult images (default 10), the
source text is truncated head+marker+tail BEFORE rendering. Classifier
picks the truncation strategy:
- structured (JSON/YAML/diff): head-only, tail is repeating elements
- log (timestamps / [LEVEL] prefixes): 60% head + 40% tail
- other (prose, dumps): same head/tail split
The marker tells the model what was elided so it can reason about the
gap: '[ pixelpipe paging: omitted N lines (K chars) ... ]'. Keeps
requests under Anthropic's 100-image-per-request cap even when a single
tool dumps a multi-megabyte log.
2. Adaptive CHARS_PER_IMAGE. Previously hardcoded at 14_100 (Unifont 10px
@ cell 5×11). Now derived at module load from ATLAS_CELL_H + render.ts
constants. When gen-atlas regenerates with a different font/size, the
break-even threshold automatically updates: at Cozette 4×7 the chars/
image jumps from 14.1k → 22.2k and the break-even drops from ~10k → ~3k.
Single source of truth in src/core/.
Wires:
- TransformOptions.maxImagesPerToolResult (default 10)
- TransformInfo.truncatedToolResults + omittedChars
- TrackEvent.truncated_tool_results + omitted_chars (emit when > 0)
- Two new exported helpers: estimateImageCount, classifyContent, truncateForBudget
- Paging fires before image-encoding at both tool_result branches
(string content and array-of-text-blocks content)
Tests: +28 paging-specific (paging.test.ts), 199/199 total green.
Bundle delta: negligible (~3 KB raw, ~1 KB gzipped). 488 KB dist gzipped.
Closes the paging-implementer worktree merge that was deferred earlier.
|
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|
teamchong
|
b5d768fcdc |
dashboard: sessions UI + stats panel + smooth updates + cleanup
Pivot from prior CLI subcommands (stats, sessions) to dashboard-based UI. bin/cli.js becomes a minimal proxy starter; all functionality lives at http://127.0.0.1:47821/. New endpoints: GET /api/sessions.json — session list + Claude Code mapping GET /api/sessions/:id.json — session detail (bodies redacted by default) POST /api/sessions/prune — dry-run-first cleanup with atomic rewrite GET /api/disk.json — events.jsonl + 4xx-bodies disk usage GET /api/stats.json — full-history aggregate (replaces CLI 'stats') GET /sessions/:id — HTML detail page Dashboard HTML extended with sessions panel + stats panel + cleanup panel. Smooth-poll: 2s tick for legacy live counters, 5s tick for sessions/stats/disk. Session rows diff-rendered (no full-table flash). Destructive actions show window.confirm() with dry-run preview of impact. Session mapping: synthetic ID from first_user_sha8 (already on every event) + opportunistic enrichment by fingerprinting against ~/.claude/projects/*.jsonl. Falls back gracefully if Claude Code's session dir is missing. Atomic events.jsonl rewrite (write to .tmp, fsync, rename) preserved from the prior CLI design — trigger is now HTTP POST. +51 new tests (33 sessions + 18 dashboard-api). 149/149 total. |
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|
teamchong
|
e7489ca1fb |
transform: per-block compression break-even check + honest dashboard
URGENT production-cost fix. Empirical data (orig_chars=169779, image_count=88)
showed we were paying ~220k image tokens to replace ~42k text tokens — a
net LOSS of ~178k tokens per request. Dashboard hid this via Math.max(0,...).
Two changes ship together:
1. isCompressionProfitable(textLen) gate in transform.ts. Before any
per-block image encode (static slab, reminder, tool_result), compute:
estImages × TOKENS_PER_IMAGE vs textLen / CHARS_PER_TOKEN
Compress only when the image side wins. Constants:
CHARS_PER_IMAGE = 14100 (Unifont 10px, cell 5×11, 100 cols)
CHARS_PER_TOKEN = 4
TOKENS_PER_IMAGE = 2500 (empirical, history-researcher round 3)
Result: blocks under ~10k chars stay as text. Static slab still
compresses (always above break-even).
2. Coarse thresholds bumped as fast-path:
minReminderChars 1000 → 5000
minToolResultChars 5000 → 10000
(Cover the obvious-no cases without invoking the precise check.)
3. Dashboard honesty: removed Math.max(0,...) clamp in baselineCost().
Negative savings now display as negative (no more hidden cost-bleed).
4. Telemetry: passthrough_reasons.below_threshold + .not_profitable
counters surface how often each gate fires.
After restart, dashboard 'saved' should jump from clamped-0 to a real
positive number (~1-3% on aggregate; static slab compression is the
only block consistently profitable at our current cell).
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teamchong
|
e328c93d52 |
atlas: bit-pack pixel storage (1 bit/pixel) for 3.15× bundle shrink
Unifont glyphs are inherently 1-bit (every pixel is 0 or 255). Storing as
8-bit bytes wasted 7 bits per pixel.
Changes:
- scripts/gen-atlas.ts: emit ATLAS_PIXELS as bit-packed MSB-first. OFFSETS
now indexes bits not bytes. Per-cell paint thresholds R-channel at 128
defensively (Unifont is already 0/255).
- src/core/render.ts:blitGlyph: byte read replaced with bit extraction
(~3 extra ops per pixel; negligible). max() blending removed since bit
data is binary, no AA edges, no glyph overlap.
- src/core/atlas.ts: regenerated with the new format. Header comment
documents the bit-extraction formula.
- tests/render.test.ts: +1 structural assertion that ATLAS_PIXELS.byteLength
matches the bit-packed total.
Bundle size:
atlas.ts raw: 5.47 MB → 1.06 MB (5.2× shrink)
atlas.ts gzip: 1.55 MB → 479 KB (3.2× shrink)
dist gzipped: 1.57 MB → 488 KB (3.15× shrink, well under Workers
free-tier 1 MB cap)
Pre-deflate shrink is 8× (theoretical max). The 3.15× post-deflate
result reflects that deflate was already exploiting long runs of 0/255
in the 8-bit data; the bit-packed bytes are denser and less compressible.
Render output is byte-identical to pre-bit-pack (storage format change
only). 108/108 vitest, 4/4 shell tests, typecheck + build clean.
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teamchong
|
efcd2a5e3e |
render: R1 whitespace minify before wrap
Adds minifyForRender() as step 1 of wrapLines() pipeline. Strips trailing whitespace per line and collapses 4+ consecutive newlines to 3 (= 2 blank lines). Leading whitespace + mid-line spaces preserved (structural). HANDOFF item R1 predicted ~1.5-2× chars per image. Empirical measurement on real corpora (v3 corpus, all .md docs, all .ts source, 2.3 MB live conversation jsonl) showed 0% reduction — modern editors strip trailing whitespace on save by default. R1 is shipped as defensive infrastructure that fires when log-dump-heavy / unminified content arrives. +9 tests covering trailing-strip, blank-line collapse, structural-space preservation, and combined-with-tab-expansion pipeline. 107/107 vitest. |
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teamchong
|
cc7f0ed4b8 |
tests: align tab-expansion test expectations with the visible-arrow shape
Previous test expectations had been written against an older silent-space tab expansion. The arrow form (\t → "→" + padding to tab stop) was already in src/core/render.ts; this just brings the tests into agreement. Includes 7 expandTabsInLine tests covering col 0/1/2/3 tab boundaries, the fast-path for tab-free lines, and EAW-aware width counting for tabs after CJK glyphs. Total: 98/98 vitest passing. |
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teamchong
|
f199640bdc |
ship Unifont @ 10px multilingual rendering + 400 diagnosis fixes
- Switch font: JetBrains Mono @ 15px → Unifont 16.0.04 @ 10px. Sparse atlas with double-width EAW dispatch for CJK. Full BMP profile (35,501 glyphs) covers Latin/Cyrillic/Greek/Hebrew/Arabic/CJK/Hangul plus Letterlike, Misc Technical, Block Elements, Geometric Shapes, Misc Symbols, Dingbats, Enclosed Alphanumerics, all box-drawing. - Fix cell-height bug (was hardcoded 9; now probed from font metrics via Math.ceil(maxAscent+maxDescent)). Previously clipped the top 2 rows off every CJK glyph since the original Unifont ship. - Expand tabs to spaces with 4-column tab stops, EAW-aware. Was the silent-drop source for 99.6% of dropped chars in production. - Add dropped_codepoints_top telemetry (top 20 per event, only emitted when drops > 0) so future coverage gaps surface in events.jsonl. - Raise minToolResultChars 2000→5000 and minReminderChars 1000→2000 to stop net-losing tokens on small compressions, per ~2,500 tok/img empirical measurement (N=33 cold-miss events). - Fix dashboard per-image-cost formula: was pngBytes/375 (~190 tok), now imageCount * 2500 (the measured empirical rate). Reduces the inflated "tokens saved" headline to honest numbers. - Schema-stub fix in compressSchemas path: preserveSchemaShell() retains type / properties / required / enum / oneOf / anyOf / $ref / numeric constraints recursively (depth 20), strips only descriptions and metadata. Prevents 400 errors on first-tool-call requests. - Capture full gzipped 4xx body + per-event req_body_sha8 for upstream error diagnosis. Sidecar to ~/.pixelpipe/4xx-bodies/ when over 32 KB inline cap. Workers-safe via CompressionStream + Web Crypto. - scripts/restart.sh: pnpm-aware one-command kill+rebuild+start with graceful SIGTERM→SIGKILL escalation, build-failure abort, port-in-use precheck, --no-build flag for fast iteration. Shell-tested. - Bundle 1.58 MB gzipped on Node. 91/91 vitest + 4/4 shell tests. |
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teamchong
|
241cdbb6aa |
build: pin pnpm@10.21.0 as the package manager
- Add `packageManager` field so corepack uses the pinned version - Add `preinstall: npx only-allow pnpm` guard to block accidental `npm install` (npm exits non-zero with a clear redirect) - Add `engines.pnpm: >=10` requirement - Bundles the previously-uncommitted restart + test:restart script entries (already in use via the diagnostic-instrumentation slice) |
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teamchong
|
b6f2b65b9a |
dashboard: correct the docstring's renderer-width number
Per the renderer-analyst's audit of src/core/render.ts, our renderer's fixed width is `2*PAD_X + DEFAULT_COLS*ATLAS_CELL_W = 8 + 100*9 = 908px`, NOT the 1466 the previous docstring claimed (which mistook Anthropic's max image width for ours). True worst-case is 908×1568/750 ≈ 1898 tokens, a typical image at this workload is ~170 tokens (well under what the byte-derived estimator computes already). No formula change — `estImageTokens(pngBytes) = pngBytes/375` was always size-agnostic. This is a comment-only fix so a future reader doesn't repeat the mistake. |
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teamchong
|
b49764e64c |
docs: add TRANSFORM_INFO.md (compression strategy reference)
A single canonical document explaining how pixelpipe compresses Claude Code requests end-to-end. Covers, in order: 1. Why this proxy exists 2. The static / dynamic split (DYNAMIC_BLOCK_TAGS, KNOWN_STATIC_TAGS) 3. What the final request looks like (placement='user' layout) 4. The cache_control budget (the one invariant that matters: ttl='1h') 5. Per-message compressions (reminders + tool_results, no cache_control) 6. Determinism and fingerprints (systemSha8, claudeMdSha8, firstUserSha8) 7. The unknown-tag canary 8. The savings math (effectiveCost / baselineCost from src/dashboard.ts) 9. What deliberately did NOT get built 10. Wiring map Intended as the file a new contributor reads after CLAUDE.md but before touching src/core/transform.ts. HANDOFF.md is session-state and rotates; README.md is install/run; CLAUDE.md is rules; this is the architecture reference that explains WHY the code looks the way it does. Authored by the doc-writer teammate, KNOWN_STATIC_TAGS section post-edited to reflect that |
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teamchong
|
be372a0c3a |
legacy: drop python reference oracle (live savings confirmed at 98.7%)
HANDOFF item #4 was "Delete legacy/python/ — but only after #1 confirms live savings." Item #1 (live cache-rate validation) now passes: over 232 compressed POST /v1/messages calls in a 46-minute real-traffic window, cache hit rate by tokens is 98.7%, clearing the HANDOFF 60% bar by 38 points. The Python reference has done its job. Removes (1831 deletions): legacy/python/proxy.py (975) full Python proxy implementation legacy/python/diff_transform.py (213) body-diff parity oracle legacy/python/cli.js (170) shim legacy/python/visual_compare.py (150) PNG-diff parity oracle legacy/python/diff_render.py (136) render-only parity oracle legacy/python/gen_atlas.py ( 75) atlas generator (TS port owns this now via scripts/gen-atlas.ts) legacy/python/install.js ( 50) installer shim legacy/README.md ( 35) Comment / doc updates to remove references: README.md drops the "## Legacy" section CLAUDE.md drops the "## Parity oracle" section + tree entry src/core/transform.ts header comment no longer cites legacy/python src/dashboard.ts header comment notes the formulas were ported, not where from docs/TRANSFORM_INFO.md edits land in the separate TRANSFORM_INFO commit The byte-output determinism the Python oracle existed to guard against is now pinned by tests/render.test.ts ("renders identical input to byte- identical output (determinism = cacheability)") and the systemSha8 fingerprint in every JSONL row. If a future change ever breaks determinism, the test will catch it before merge, and the production-deployed cache hit rate will catch it within minutes after. Gates: typecheck clean, 38 tests pass, build clean dist/node.js. |
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teamchong
|
96e3422250 |
dashboard: derive image-token estimate from actual PNG bytes, not worst-case constant
The dashboard's `baselineCost` was using a hardcoded `IMAGE_TOKEN_ESTIMATE
= 3066` per image (the worst-case 1466×1568 image at Anthropic's
~ceil(W·H/750) rate). Our renderer almost never produces full-size
images — typical workload renders ~1466×90 px per image — so the constant
overestimates by roughly 15×. Concrete effect: with `image_count = 90`
and `orig_chars = 173835`, `imgTokensEst = 275940` overwhelms
`txtReplaced = 43459`, the `extraText = max(0, …)` clamp collapses to 0,
and the dashboard reported `saved_pct = 0%` on a session that was
actually getting 98.7% cache hit rate by tokens (savings-analyst
findings against the user's real events file).
Replace the constant with a per-image estimate derived from actual PNG
byte count:
raw_pixels ≈ png_bytes × 2 (grayscale zlib compresses dense glyph
rows to ~50% of raw)
token_est ≈ raw_pixels / 750 (Anthropic's published rate)
= png_bytes / 375
Helper `estImageTokens(pngBytes)` encodes this. `baselineCost` now takes
`imageBytes` (which TransformInfo has always carried) instead of
`imageCount`. The `expected_image_tokens` RecentRow field — shown in the
dashboard "img tok" column — is updated to the same estimator so live
and replayed rows agree. The legacy `IMAGE_TOKEN_ESTIMATE` constant is
removed; nothing else referenced it.
No test changes — existing tests don't exercise saved_pct math (the
dashboard module isn't in the test surface) and the formula change is
purely an estimator refinement. Verified against the live events file:
saved_pct now shows positive numbers reflecting the actual cache wins.
Open follow-up: the renderer is producing many short images instead of
fewer tall ones (~30 wire-bytes per source-text-char), and that's a
separate render.ts investigation. This commit doesn't change that — it
just makes the dashboard math honest about the current renderer output.
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teamchong
|
e219b37cd5 |
transform: KNOWN_STATIC_TAGS allowlist (silence <types> canary)
The canary in splitStaticDynamic flags tag-shaped blocks in the static slab that aren't in DYNAMIC_BLOCK_TAGS — designed to catch a new Claude Code release that ships a per-turn tag we'd accidentally bake into the cached image. In production it has been firing on `<types>` for 93% of real requests (125 of 134 in the user's events log), which is noise: `<types>` is part of Claude Code's built-in tool documentation, not a per-turn rotation. Add a second list, KNOWN_STATIC_TAGS, that mirrors DYNAMIC_BLOCK_TAGS in shape. The unknown-tag computation now subtracts BOTH lists, so a tag is only "unknown" when it's in neither the per-turn set nor the known-static set. Seed KNOWN_STATIC_TAGS with ['types']. Updates the warn log in src/node.ts to mention both options so a reviewer of a NEW unknown tag knows which list to extend. Adds a regression test pinning that <types> in the static slab no longer produces info.unknownStaticTags. |
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teamchong
|
a5f61ba6ee |
transform: compress large tool_result text content across user messages
Tool results (Bash output, Read file contents, etc.) accumulate as the
session grows. Once produced they're static — same bytes turn after turn
— but the model gets billed for them on every call until they fall out
of cache. Image-rendering them at the source compounds the savings
across the whole conversation.
Walks ALL user messages (not just the first — that's the reminder-
compression scope) and rewrites tool_result blocks whose content is at
or above minToolResultChars (default 2000, matching legacy/python/proxy.py):
- content: string → replace with image block(s) (whole content goes)
- content: array → walk inner blocks, replace each TextBlock ≥ threshold
with image blocks; leave ImageBlocks and short text
alone
- is_error: true → leave the whole block alone. Anthropic rejects
images inside is_error tool_results
(`tool_result with is_error=true cannot contain images`).
Like reminder compression these images carry NO cache_control — the
system+tools image is our only breakpoint. The savings are 65-73% of
input tokens per compressed block on Opus 4.7.
Wire-up:
- src/core/transform.ts: TransformOptions.compressToolResults (default
true) + minToolResultChars (default 2000). TransformInfo.toolResultImgs
counter. Reuses textToImageBlocks / approxBlockBytes from commit 3.
- src/core/tracker.ts: TrackEvent.tool_result_imgs flows from the
transform info.
- src/worker.ts: COMPRESS_TOOL_RESULTS + MIN_TOOL_RESULT_CHARS env vars.
- src/node.ts: CliOpts fields, parseCli cases (--no-tool-results,
--min-tool-result-chars), help text, env-var summary, `tr+N` in the
per-request console line when tool_result_imgs > 0, and tool_results=
in the startup config summary.
Tests:
- "compresses large tool_result text content across user messages"
confirms info.toolResultImgs ≥ 1, the tool_result block's content
becomes an array of image blocks, and those images carry no
cache_control.
- "leaves is_error tool_results untouched (Anthropic forbids images
there)" confirms info.toolResultImgs is 0 and the content stays a
plain string when is_error: true.
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teamchong
|
40037568e2 |
transform: compress <system-reminder> blocks in the first user message
Claude Code re-injects the same long <system-reminder> blocks (CLAUDE.md
hints, task-tools reminders, the dynamic skills list, etc.) into the
FIRST user message on every turn. They're text, so they're not part of
the system+tools image we already cache — they hit the wire fresh every
turn. This rewrite renders any reminder block ≥ minReminderChars (1000
by default, matching legacy/python/proxy.py) to PNG images placed inside
the user message content array, just like the static slab.
Why: the system+tools image is the only cache_control breakpoint we're
allowed (Anthropic caps at 4 and Claude Code uses the others). Per-block
reminder images therefore carry NO cache_control — they're per-turn
content that the model OCRs without prefix-cache benefit. The win is
token cost, not cache: reminders are 65-73% cheaper as PNG than as text,
and a typical turn has 1-3 of them.
Layout inside the first user message after compression:
[intro text] ← static (helps OCR framing)
[image block(s)] ← static; LAST has cache_control
↑ cache breakpoint (the only one)
[End of rendered context.] ← static text closer for the image
[processed existing content] ← per-turn (incl. reminder images)
Wire-up:
- src/core/transform.ts: new TransformOptions.compressReminders (default
true) + minReminderChars (default 1000). Two new helpers,
textToImageBlocks() (wraps renderTextToPngs + makeImageBlock with
no cache_control) and approxBlockBytes() (b64 → byte-count for the
imageBytes telemetry, no second base64 round-trip). The placement
='user' branch now walks `existing` and rewrites long reminders.
- src/core/tracker.ts: TrackEvent.reminder_imgs flows from
TransformInfo.reminderImgs through toTrackEvent so `pixelpipe stats`
and the dashboard can attribute compression contributions.
- src/worker.ts: COMPRESS_REMINDERS + MIN_REMINDER_CHARS env vars.
- src/node.ts: matching CliOpts, parseCli cases (--no-reminders,
--min-reminder-chars), help text, env-var summary, and `rem+N` in
the per-request console line when reminder_imgs > 0.
Tests:
- "compresses long <system-reminder> blocks in the first user message"
confirms info.reminderImgs ≥ 1, the reminder text is gone from
user-content text blocks, the user's actual prompt survives, and the
new reminder image blocks carry NO cache_control.
- "leaves short <system-reminder> blocks alone (below minReminderChars)"
confirms info.reminderImgs is 0 and the reminder text passes through
as text.
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teamchong
|
ba13bf3a42 |
dashboard: live HTML + JSON endpoints in the Node host
Ports the live dashboard from legacy/python/proxy.py into TypeScript.
Node-only by design — the Workers host doesn't expose a dashboard (use
Workers Logs / Logpush for that).
New module src/dashboard.ts:
- DashboardState keeps a 50-entry ring buffer of recent requests, plus
running totals for the savings-vs-baseline computation (same formula
as the Python: input + cache_create*1.25 + cache_read*0.10). One
latest PNG is held in memory for the preview pane.
- Replay-on-startup: reads the tail of ~/.pixelpipe/events.jsonl so the
UI doesn't show an empty table after a process restart. Cumulative
totals are NOT replayed (file may have rotated; double-counting beats
starting from zero badly here? — no, starting fresh is the lesser
evil after rotation, hence "best-effort replay of the ring buffer
only").
- Four HTTP handlers: serveHtml (the inline dashboard page),
serveStats (JSON aggregate), serveRecent (JSON ring buffer),
servePng (the latest preview image). dashboardPath() classifies a
path so the Node server can intercept before the proxy handler.
- Inline HTML uses CSS object-position to crop the preview at the
image's native resolution — no server-side PNG decode needed.
Plumbing changes:
- src/core/transform.ts: capture info.firstImagePng / firstImageWidth /
firstImageHeight after rendering. NOT persisted to JSONL; toTrackEvent
drops them. Memory cost is bounded (only the latest image survives,
the dashboard replaces on every update).
- src/node.ts: import DashboardState, instantiate, seed via replay,
call dashboard.update(e) inside onRequest BEFORE tracker.emit (the
tracker strips firstImagePng). The HTTP handler intercepts the four
dashboard paths and answers from DashboardState; everything else
falls through to the proxy.
- src/node.ts / src/worker.ts: bump the CLI/env default for PLACEMENT
from 'system' to 'user' so the runtime path matches transform's
default (
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teamchong
|
e0950efa6f |
transform: default to placement='user' and stamp ttl='1h' on image cache_control
Two protocol-correctness fixes that have to ship together. 1. **Default placement: 'system' → 'user'.** Anthropic's `system` field is typed as `string | TextBlock[]` — image blocks there come back as `400 system.N.type: Input should be 'text'`. Images must go into a user-message content array. 2. **ttl='1h' on the image's cache_control.** Anthropic enforces the rule "ttl='1h' must not come after ttl='5m'" in processing order (tools → system → messages). Claude Code marks its own user-message content with ttl='1h'; if we leave ttl unset it defaults to '5m', our block lands first in processing order, and the request 400s the moment Claude Code's own 1h breakpoint shows up later in the conversation. The existing image-placement tests now look in messages[0].content instead of out.system, and a new test pins the ttl='1h' invariant directly. |