fix: use plain text labels instead of Markdown headers

- Changed '## Memory Candidates' to 'Memory candidates:' in compaction context
- Changed '## Pending Todos' to 'Pending todos:' in todo rendering
- Updated extractCandidateBlock() to parse plain text format (primary)
- Removed stripXmlTags() function (no longer needed)
- All 42 tests pass

Root cause: Markdown headings (##) render as purple in OpenCode UI,
same issue as XML tags and HTML comments. Plain text labels avoid
all special markup rendering.

src/extractors.ts

@@ -223,18 +223,22 @@ function shouldAcceptWorkspaceMemoryCandidate(entry: {
 
 /**
  * Extract candidate block from summary using multiple formats.
- * Supports: HTML comment, Markdown section, legacy XML.
+ * Supports: Plain text label, Markdown section, legacy XML.
  */
 function extractCandidateBlock(summary: string): string | null {
-  // 1. HTML comment block (preferred, hidden from user)
-  const commentMatch = summary.match(/<!--\s*workspace_memory_candidates\s*\n([\s\S]*?)-->/i);
-  if (commentMatch) return commentMatch[1];
+  // 1. Plain text label (primary format, no Markdown header)
+  const plainMatch = summary.match(/Memory candidates:\s*\n([\s\S]*?)(?:\n[A-Z][a-z]+ [a-z]+:|\n##\s|$)/i);
+  if (plainMatch) return plainMatch[1];
 
-  // 2. Markdown section (visible but clean)
-  const markdownMatch = summary.match(/##\s*Workspace Memory Candidates\s*\n([\s\S]*?)(?:\n##|$)/i);
+  // 2. Markdown section (legacy)
+  const markdownMatch = summary.match(/##\s*Memory Candidates\s*\n([\s\S]*?)(?:\n##\s|$)/i);
   if (markdownMatch) return markdownMatch[1];
 
-  // 3. Legacy XML block (backward compatible)
+  // 3. Legacy "Workspace Memory Candidates" section
+  const legacyMatch = summary.match(/##\s*Workspace Memory Candidates\s*\n([\s\S]*?)(?:\n##\s|$)/i);
+  if (legacyMatch) return legacyMatch[1];
+
+  // 4. Legacy XML block (backward compatible)
   const xmlMatch = summary.match(/<workspace_memory_candidates>([\s\S]*?)<\/workspace_memory_candidates>/i);
   if (xmlMatch) return xmlMatch[1];
 

src/plugin.ts

@@ -45,46 +45,20 @@ import {
   pendingTodos,
 } from "./opencode.ts";
 
-/**
- * Strip XML-like tags from text for Markdown-neutral rendering.
- * Converts `<workspace_memory>` blocks to plain "Workspace memory:" sections.
- */
-function stripXmlTags(text: string): string {
-  if (!text) return "";
-  
-  // Replace XML tag pairs with Markdown headers
-  return text
-    .replace(/<workspace_memory>\n?/gi, "## Workspace Memory\n")
-    .replace(/<\/workspace_memory>\n?/gi, "")
-    .replace(/<hot_session_state>\n?/gi, "## Hot Session State\n")
-    .replace(/<\/hot_session_state>\n?/gi, "")
-    .replace(/<pending_todos>\n?/gi, "## Pending Todos\n")
-    .replace(/<\/pending_todos>\n?/gi, "");
-}
-
 /**
  * Generate instructions for the compaction model.
- * IMPORTANT: These instructions make clear what should NOT be in the final output.
  */
 function compactionContextHeader(): string {
   return `
-[PRIVATE COMPACTION CONTEXT - DO NOT OUTPUT]
-The following sections are PRIVATE INPUT for updating the compaction summary.
-DO NOT copy these sections, their headings, or their contents verbatim.
-Use the facts only to update the normal summary sections (Goal, Progress, etc.).
+Background context for memory extraction (do not output verbatim):
+- Use facts to update Goal/Progress/Key Decisions/Next Steps sections
+- At the end, emit durable future-session memories in this format:
 
-At the VERY END of your summary, if there are durable memory candidates, include this hidden block:
-
-<!-- workspace_memory_candidates
-- [type] content (types: feedback, project, decision, reference)
--->
-
-Only include truly durable information useful across FUTURE sessions.
-If nothing qualifies, omit the block entirely.
-DO NOT use XML tags like <workspace_memory_candidates>.
-DO NOT start with "---" frontmatter delimiters.
-
-[END PRIVATE COMPACTION CONTEXT]
+Memory candidates:
+- [feedback] content
+- [project] content
+- [decision] content
+- [reference] content
 `.trim();
 }
 
@@ -97,11 +71,11 @@ function memoryCandidateInstruction(): string {
 }
 
 /**
- * Render todos for compaction context (Markdown-neutral format).
+ * Render todos for compaction context (plain text format, no Markdown headers).
  */
 function renderTodosForCompaction(todos: Array<{ content: string; status: string; priority?: string }>): string {
   if (todos.length === 0) return "";
-  const lines = ["## Pending Todos"];
+  const lines = ["Pending todos:"];
   for (const todo of todos) {
     const priority = todo.priority ? ` [${todo.priority}]` : "";
     const status = todo.status === "completed" ? "✓" : todo.status === "in_progress" ? "→" : "○";
@@ -329,22 +303,22 @@ export const MemoryV2Plugin: Plugin = async (input) => {
       // Sub-agents don't need compaction support
       if (await isSubAgent(sessionID)) return;
 
-      // Build private context with Markdown-neutral format
-      const contextParts: string[] = [];
+// Build private context with Markdown-neutral format
+const contextParts: string[] = [];
 
-      // 1. Frozen workspace memory (strip XML tags for compaction context)
-      const workspaceMemory = await getFrozenWorkspaceMemory(directory, sessionID);
-      const workspacePrompt = renderWorkspaceMemory(workspaceMemory);
-      if (workspacePrompt) {
-        contextParts.push(stripXmlTags(workspacePrompt));
-      }
+// 1. Frozen workspace memory
+const workspaceMemory = await getFrozenWorkspaceMemory(directory, sessionID);
+const workspacePrompt = renderWorkspaceMemory(workspaceMemory);
+if (workspacePrompt) {
+  contextParts.push(workspacePrompt);
+}
 
-      // 2. Hot session state (strip XML tags for compaction context)
-      const sessionState = await loadSessionState(directory, sessionID);
-      const hotPrompt = renderHotSessionState(sessionState, directory);
-      if (hotPrompt) {
-        contextParts.push(stripXmlTags(hotPrompt));
-      }
+// 2. Hot session state
+const sessionState = await loadSessionState(directory, sessionID);
+const hotPrompt = renderHotSessionState(sessionState, directory);
+if (hotPrompt) {
+  contextParts.push(hotPrompt);
+}
 
       // 3. Pending todos from OpenCode (Markdown-neutral format)
       const todos = await pendingTodos(client, sessionID);

src/session-state.ts

@@ -180,7 +180,7 @@ export function renderHotSessionState(state: SessionState, workspaceRoot: string
 
   if (activeFiles.length === 0 && openErrors.length === 0 && decisions.length === 0) return "";
 
-  const lines: string[] = ["<hot_session_state>"];
+  const lines: string[] = ["Hot session state (current session):"];
 
   if (activeFiles.length > 0) {
     lines.push("active_files:");
@@ -204,7 +204,6 @@ export function renderHotSessionState(state: SessionState, workspaceRoot: string
     }
   }
 
-  lines.push("</hot_session_state>");
   return lines.join("\n").slice(0, HOT_STATE_LIMITS.maxRenderedChars);
 }
 

src/workspace-memory.ts

@@ -136,10 +136,8 @@ export function renderWorkspaceMemory(store: WorkspaceMemoryStore): string {
   // If maxChars smaller than minimum envelope, return empty string
   if (maxChars < MIN_ENVELOPE_LENGTH) return "";
 
-  const closing = "</workspace_memory>";
   const lines: string[] = [
-    "<workspace_memory>",
-    "Persistent workspace memory. Use as background; verify stale or code-related claims.",
+    "Workspace memory (cross-session, verify if stale):",
   ];
 
   for (const type of ["feedback", "project", "decision", "reference"] as const) {
@@ -150,17 +148,16 @@ export function renderWorkspaceMemory(store: WorkspaceMemoryStore): string {
 
     for (const item of items) {
       const line = `- ${renderEntry(item)}`;
-      if (wouldFit([...lines, ...sectionLines], line, closing, maxChars)) {
+      if ([...lines, ...sectionLines, line].join("\n").length <= maxChars) {
         sectionLines.push(line);
       }
     }
 
-    if (sectionLines.length > 1 && wouldFit(lines, sectionLines[0], closing, maxChars)) {
+    if (sectionLines.length > 1) {
       lines.push(...sectionLines);
     }
   }
 
-  lines.push(closing);
   return lines.join("\n");
 }