diff --git a/HELDOUT-REPORT.md b/HELDOUT-REPORT.md
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+# Held-out retrieval eval
+
+Independent eval for issue #24. Questions were written from the 17 verbatim raw sources under:
+
+`/Users/ved/Developer/grimoire/.growth/truth/workspaces/agent-sdk-claude/raw/uncategorized/`
+
+Wiki contents were not read; only wiki slugs were listed. Excluded files from `SPEC.md` were not opened or modified. Ranking code was not tuned.
+
+## Commands
+
+```sh
+npm run build
+node scripts/retrieval-eval.mjs /Users/ved/Developer/grimoire/.growth/truth/workspaces/agent-sdk-claude test/fixtures/retrieval-questions.heldout.json --no-fail
+npm test
+```
+
+## Results
+
+| Set | Present top-1 | Present top-3 | Absent abstain | All top-1-or-abstain | All top-3-or-abstain | Gate |
+| --- | ---: | ---: | ---: | ---: | ---: | --- |
+| Tuned set from PR #21 | 10/10 | 10/10 | n/a | 10/10 | 10/10 | PASS |
+| Held-out set | 9/10 | 10/10 | 0/2 | 9/12 | 10/12 | FAIL |
+
+## Per-question output
+
+| ID | Coverage | Top-1 | Top-3 | No-hit | Expected | Returned |
+| ---: | --- | --- | --- | --- | --- | --- |
+| 1 | present | yes | yes | - | `permissions-and-approval-control` | `permissions-and-approval-control`, `hooks`, `production-security-and-sandboxing` |
+| 2 | present | yes | yes | - | `custom-tools-in-process-mcp` | `custom-tools-in-process-mcp`, `agent-loop-and-turns`, `hooks` |
+| 3 | present | yes | yes | - | `file-checkpointing` | `file-checkpointing`, `permissions-and-approval-control`, `what-is-the-agent-sdk` |
+| 4 | present | yes | yes | - | `external-mcp-integration` | `external-mcp-integration`, `custom-tools-in-process-mcp`, `tool-search` |
+| 5 | present | - | yes | - | `hosting-and-deployment-patterns` | `sessions-continue-resume-fork`, `runtime-and-subprocess-architecture`, `hosting-and-deployment-patterns` |
+| 6 | present | yes | yes | - | `observability-opentelemetry` | `observability-opentelemetry`, `hooks`, `authentication-and-providers` |
+| 7 | present | yes | yes | - | `migration-from-claude-code-sdk` | `migration-from-claude-code-sdk`, `what-is-the-agent-sdk`, `runtime-and-subprocess-architecture` |
+| 8 | present | yes | yes | - | `sessions-continue-resume-fork` | `sessions-continue-resume-fork`, `runtime-and-subprocess-architecture`, `file-checkpointing` |
+| 9 | present | yes | yes | - | `subagents` | `subagents`, `observability-opentelemetry`, `permissions-and-approval-control` |
+| 10 | present | yes | yes | - | `tool-search` | `tool-search`, `external-mcp-integration`, `custom-tools-in-process-mcp` |
+| 11 | absent | - | - | - | absent | `what-is-the-agent-sdk`, `migration-from-claude-code-sdk`, `runtime-and-subprocess-architecture` |
+| 12 | absent | - | - | - | absent | `what-is-the-agent-sdk`, `custom-tools-in-process-mcp`, `hosting-and-deployment-patterns` |
+
+## Finding
+
+The independent set does not reproduce the tuned set's 10/10 gate. Retrieval is strong for covered topics at top-3, but the current behavior does not abstain on absent topics: both absent questions returned wiki articles instead of no hit.
+
+## Test status
+
+`npm test` passed: 23 test files, 368 tests.
diff --git a/test/fixtures/retrieval-questions.heldout.json b/test/fixtures/retrieval-questions.heldout.json
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+[
+  {
+    "question": "If I set a PreToolUse hook to allow a command, can a deny rule still block it later in the permission flow?",
+    "expectedSlug": "permissions-and-approval-control"
+  },
+  {
+    "question": "For a custom in-process tool, what happens to the agent loop if my handler throws instead of returning an error result?",
+    "expectedSlug": "custom-tools-in-process-mcp"
+  },
+  {
+    "question": "Can file rewind undo changes made by a shell command like sed, or only SDK edit operations?",
+    "expectedSlug": "file-checkpointing"
+  },
+  {
+    "question": "Where should I check for failed MCP server connections before letting an agent start using those tools?",
+    "expectedSlug": "external-mcp-integration"
+  },
+  {
+    "question": "When hosting many active agent sessions, why do I need separate working directories or per-session cwd values?",
+    "expectedSlug": "hosting-and-deployment-patterns"
+  },
+  {
+    "question": "Which telemetry switch records full tool inputs and outputs, and why should it stay off unless the pipeline is approved?",
+    "expectedSlug": "observability-opentelemetry"
+  },
+  {
+    "question": "What changed in the rename from the old Claude Code SDK packages to the Agent SDK packages?",
+    "expectedSlug": "migration-from-claude-code-sdk"
+  },
+  {
+    "question": "How can I fork a conversation to try another direction without changing the original session history?",
+    "expectedSlug": "sessions-continue-resume-fork"
+  },
+  {
+    "question": "If a subagent needs to run without seeing the parent conversation history, what information must the parent provide?",
+    "expectedSlug": "subagents"
+  },
+  {
+    "question": "Why might enabling deferred tool discovery improve both prompt size and tool selection once a server exposes hundreds of tools?",
+    "expectedSlug": "tool-search"
+  },
+  {
+    "question": "How do I configure vector embedding dimensions and chunk overlap for the Agent SDK retriever?",
+    "expectedSlug": null
+  },
+  {
+    "question": "Which managed Postgres schema does the Agent SDK create for storing durable task queues?",
+    "expectedSlug": null
+  }
+]