fix: clean up set_reflection implementation (#134)

- Remove unused toolReflectionPrompt parameter from buildSelfAssessmentPrompt
- Add truncation warning in executeSetReflection when guidance exceeds 4000 chars
- Rename resolveReflectionPrompt → resolveReflectionPromptPrecedence for consistency
- Add unit tests for buildToolReflectionGuidanceSection edge cases

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: engineer

reflection-3.ts

@@ -210,7 +210,7 @@ function buildToolReflectionGuidanceSection(toolReflectionPrompt: string | null)
   return `\n## Tool Reflection Guidance\n${toolReflectionPrompt.slice(0, 4000)}\n`
 }
 
-function resolveReflectionPrompt(
+function resolveReflectionPromptPrecedence(
   filePrompt: string | null,
   toolReflectionPrompt: string | null,
   defaultPrompt: string
@@ -1054,8 +1054,7 @@ function buildSelfAssessmentPrompt(
   context: TaskContext,
   agents: string,
   lastAssistantText?: string,
-  attemptCount?: number,
-  toolReflectionPrompt?: string | null
+  attemptCount?: number
 ): string {
   const safeContext = {
     ...context,
@@ -1080,8 +1079,6 @@ function buildSelfAssessmentPrompt(
   const attemptSection = currentAttempt > 0
     ? `\n## Reflection History\n- This is reflection attempt ${currentAttempt + 1}/${MAX_ATTEMPTS} for this task.\n- Previous reflections found the task incomplete.\n- If you are repeating the same actions without progress, set "stuck": true and explain what is blocking you.\n`
     : ""
-  const toolGuidanceSection = buildToolReflectionGuidanceSection(toolReflectionPrompt || null)
-
   return `SELF-ASSESS REFLECTION-3
 
 You are evaluating an agent's work against workflow requirements.
@@ -1097,7 +1094,6 @@ Analyze the task context, the agent's last response, and the tool signals to det
 ## Tool Commands Run
 ${safeContext.toolsSummary}
 ${assistantSection}${attemptSection}
-${toolGuidanceSection}
 ${agents ? `## Project Instructions\n${agents.slice(0, 800)}\n\n` : ""}Return JSON only:
 {
   "task_summary": "brief description of what was done",
@@ -1571,7 +1567,9 @@ export const Reflection3Plugin: Plugin = async ({ client, directory }) => {
       return `Current tool-provided reflection guidance:\n${toolReflectionPrompt}`
     }
     toolReflectionPrompt = guidance
-    return "Set tool-provided reflection guidance for this runtime. It will be used when no .reflection.md/reflection.md file override exists."
+    const msg = "Set tool-provided reflection guidance for this runtime. It will be used when no .reflection.md/reflection.md file override exists."
+    if (guidance.length > 4000) return `${msg}\n\nNote: guidance exceeds 4000 chars and will be truncated when applied to reflection prompts.`
+    return msg
   }
 
   let setReflectionTool: any = null
@@ -1650,7 +1648,7 @@ export const Reflection3Plugin: Plugin = async ({ client, directory }) => {
           lastAssistantText,
           currentAttemptCount
         )
-        const resolvedPrompt = resolveReflectionPrompt(customPrompt, toolReflectionPrompt, defaultReflectionPrompt)
+        const resolvedPrompt = resolveReflectionPromptPrecedence(customPrompt, toolReflectionPrompt, defaultReflectionPrompt)
         const reflectionPrompt = resolvedPrompt.prompt
         const effectiveToolReflectionPrompt = resolvedPrompt.effectiveToolReflectionPrompt
 

test/reflection-3.unit.test.ts

@@ -96,6 +96,39 @@ describe("reflection-3 unit", () => {
     assert.ok(!resolved.prompt.includes("TOOL REFLECTION OVERRIDE"))
   })
 
+  describe("set_reflection tool helpers", () => {
+    it("buildToolReflectionGuidanceSection(null) => empty string", () => {
+      assert.strictEqual(buildToolReflectionGuidanceSection(null), "")
+    })
+
+    it("buildToolReflectionGuidanceSection(\"\") => empty string", () => {
+      assert.strictEqual(buildToolReflectionGuidanceSection(""), "")
+    })
+
+    it("wraps guidance in section header", () => {
+      const section = buildToolReflectionGuidanceSection("Check tests and CI")
+      assert.ok(section.startsWith("\n## Tool Reflection Guidance\n"))
+      assert.ok(section.includes("Check tests and CI"))
+    })
+
+    it("truncates guidance at 4000 chars", () => {
+      const longGuidance = "x".repeat(5000)
+      const section = buildToolReflectionGuidanceSection(longGuidance)
+      assert.ok(section.startsWith("\n## Tool Reflection Guidance\n"))
+      assert.ok(section.endsWith("\n"))
+      const body = section.replace("\n## Tool Reflection Guidance\n", "").slice(0, -1)
+      assert.strictEqual(body.length, 4000)
+      assert.strictEqual(body, "x".repeat(4000))
+    })
+
+    it("resolveReflectionPromptPrecedence returns default when no file/tool guidance", () => {
+      const resolved = resolveReflectionPromptPrecedence(null, null, "DEFAULT REFLECTION PROMPT")
+      assert.strictEqual(resolved.source, "default")
+      assert.strictEqual(resolved.prompt, "DEFAULT REFLECTION PROMPT")
+      assert.strictEqual(resolved.effectiveToolReflectionPrompt, null)
+    })
+  })
+
   it("evaluates missing tests and build requirements", () => {
     const assessment = {
       status: "complete" as const,