Reproduce Benchmark

Run a tool's or paper's benchmark harness and record what could and could not be verified.

When to Use

• User asks to reproduce or verify benchmark claims for a triaged tool or paper
• Following up on a triage or analysis where self-reported metrics need independent verification
• User provides a slug, reference path, or analysis path and says "run the benchmark"

When Not to Use

• The subject has not yet been triaged — run triage-tool or triage-paper first
• A repro file already exists in benchmarks/sources/ — report it and offer to re-run instead
• The benchmark requires live external services or paid APIs that are unavailable — set outcome to unverified and document the blocker

Recommended MCP Servers

If the benchmark harness or reported figures need to be looked up from the original paper, prefer these MCPs over WebFetch:

{
  "mcpServers": {
    "semantic-scholar": {
      "type": "stdio",
      "command": "uvx",
      "args": ["semantic-scholar-fastmcp"]
    },
    "google-scholar": {
      "type": "stdio",
      "command": "uvx",
      "args": ["google_scholar_mcp_server"]
    }
  }
}

See triage-paper for full setup guidance.

Mindset

Reproduction is a verification exercise, not a sales pitch.

1. Record what you observe: quote actual output, not what the README says the output should be.
2. Mark everything reported: any figure from the README or paper must carry (as reported). Never blend reported and verified numbers without distinguishing them.
3. Partial is better than fabricated: if only some scenarios run, record those honestly. Set outcome to partially-verified.
4. Environment matters: cold-start overhead, fixture quality, and dependency versions all affect results. Document them.

Workflow

1. Identify the subject

• Confirm the slug from the user (e.g. context-mode, jiang-llmlingua).
• Locate the reference file (references/<slug>.md) and analysis file (analysis/ANALYSIS-<slug>.md) if they exist.

2. Check for existing repro

• Search benchmarks/sources/ for <slug>-repro.md.
• If found, report it and ask whether to re-run or update in place.

3. Locate the benchmark harness

• Check the analysis file's Stage 2 ("Evaluative") section first.
• Otherwise check the reference file's "Benchmarks / self-reported metrics" section and the vendored source at tools/<slug>/.
• Record the harness file paths and any npm/make/cargo/shell invocation scripts.

4. Set up the environment

• Install dependencies required by the harness (e.g. npm install in the submodule).
• Note the OS, primary runtime version, and any other relevant environment details.
• If the tool is vendored as a submodule, record the pinned commit SHA.

5. Run the harness

• Execute the benchmark using the commands identified in step 3.
• Capture stdout/stderr. Do not suppress errors.
• If the harness fails, document the error and set outcome to failed.

6. Record results

Compare actual output against reported figures. Categorise each metric as:

• Verified — reproduced within ±10% of reported value
• Not reproduced — result differs materially from reported value; quote both
• Could not test — scenario requires unavailable infra (note why)

7. Write the repro file

Read assets/templates/REPRO-benchmark.yaml to get the required frontmatter fields and section structure. Create benchmarks/sources/<slug>-repro.md with a YAML frontmatter block (all required_fields from the template) followed by the required sections.

Set outcome to one of:

8. Back-fill the analysis file (if applicable)

If an ANALYSIS file exists and Stage 2.2 ("Independent verification") does not yet reference the repro file, add a pointer:

See [`benchmarks/sources/<slug>-repro.md`](../benchmarks/sources/<slug>-repro.md) — outcome: <outcome>.

9. Validate and report

Run the validator and summarise findings:

./scripts/validate-repro-benchmark.sh benchmarks/sources/<slug>-repro.md

Report: what was verified, what was not, and any caveats about fixture quality or environment.

Quick Commands

# Check for existing repro
ls benchmarks/sources/<slug>-repro.md 2>/dev/null || echo "not found"

# Install harness deps (vendored submodule)
cd tools/<slug> && npm install

# Run benchmark and capture output
npm run benchmark 2>&1 | tee /tmp/<slug>-benchmark-out.txt

# Validate the completed repro file
./scripts/validate-repro-benchmark.sh benchmarks/sources/<slug>-repro.md

Anti-Patterns

NEVER omit YAML frontmatter

WHY: Files without frontmatter fail schema validation and break indexing tools that rely on structured metadata.

BAD Start the file with # <slug> — Benchmark Reproduction followed by bold-text fields. → GOOD Open with --- YAML frontmatter block containing all required fields before any prose.

NEVER blend reported and verified numbers

WHY: Mixing unverified claims with observed results corrupts the research record.

BAD "Achieves 96% savings." when the harness was not run. → GOOD `"Reports 96% savings (as reported, BENCHMARK.md). Verified: 100% on 4 of 21 scenarios; remainder not run."

NEVER suppress harness errors

WHY: A silent failure looks like a clean run. Errors are data.

BAD Redirect stderr to /dev/null or omit error output from the repro file. → GOOD Quote the error verbatim in the Reproduction attempt section and set outcome to failed or partially-verified.

NEVER skip the existing repro check

WHY: Re-running an expensive benchmark without checking for a prior run wastes time and creates conflicting records.

BAD Write a new repro file without checking benchmarks/sources/. → GOOD Check first; if a file exists, report it and ask whether to re-run.

References

• Repro artifacts: YAML template · schema · validator