| name | dec-bench-run |
| description | Build and run DEC Bench scenarios, inspect results, and open the audit UI. Use when a user says "run scenario", "run eval", "benchmark", "run foo-bar-*", "run matrix", "compare agents", or asks about specific scenario results. |
DEC Bench Run
Build and run existing DEC Bench scenarios. This skill covers running scenarios, not creating them — for that, use dec-bench-create-scenario.
Before you start
Confirm the user has:
- DEC Bench CLI installed (
dec-bench list to verify)
- A local clone of the repo
- Docker running
- The right API key exported for their agent
If any of these are missing, point them to the dec-bench-quickstart skill.
List available scenarios
dec-bench list
This shows all scenarios with their tier, domain, and description.
Key values
Agents and models:
claude-code: claude-sonnet-4-20250514, claude-sonnet-4-6, claude-opus-4-6
codex: gpt-5.4
cursor: composer-2
Personas: baseline (plain language, no hints) or informed (specific tools, schemas, constraints)
Harnesses: base-rt, classic-de, olap-for-swe
Run a single scenario
dec-bench build --scenario <scenario-id>
dec-bench run --scenario <scenario-id>
The CLI validates the agent, model, and API key before building. If validation fails, it tells the user what to fix.
Specify agent and model
dec-bench build --scenario <scenario-id> --agent codex --model gpt-5.4
dec-bench run --scenario <scenario-id> --agent codex --model gpt-5.4
Defaults: --agent claude-code --model claude-sonnet-4-20250514
Specify harness
dec-bench build --scenario <scenario-id> --harness classic-de
dec-bench run --scenario <scenario-id> --harness classic-de
Default: --harness base-rt
Inspect results
dec-bench results --latest --scenario <scenario-id>
dec-bench results --run-id <run-id>
This prints gate scores, normalized score, and paths to all artifacts (stdout, trace, assertion log, session JSONL).
Open the audit UI
dec-bench audit open --scenario <scenario-id> --run-id <run-id>
Opens a local web UI with agent traces, assertion results, and run metadata.
Run the full matrix
Run all agent/harness/persona combinations:
dec-bench run --matrix --parallel auto
This validates all agent/model/key combos upfront before any Docker work.
For --parallel > 1, supply multiple provider keys via the plural env vars
so each container gets its own key:
export ANTHROPIC_API_KEYS=sk-ant-key1,sk-ant-key2
dec-bench run --matrix --parallel 2
With only the singular *_API_KEY set, the CLI warns and proceeds — expect
rate-limit errors from the provider.
Heads up: Anthropic (and most major providers) apply rate limits at the
organization level, not the key level. Two keys from the same org share
one rate-limit pool, so multi-key rotation only adds real capacity when the
keys come from different organizations. Within one org, the only ways to
get more capacity are a higher usage tier or lower --parallel.
Common issues
- Build fails with Docker error: start Docker Desktop and retry
- API key invalid: the CLI checks keys against provider APIs — verify the key is correct and not expired
- Wrong agent/model combo: the CLI rejects incompatible pairs (e.g.
--agent codex --model claude-sonnet-4-6)
- Anthropic/OpenAI rate limits during a parallel matrix run: rotation across same-org keys does not help — drop
--parallel, raise your usage tier, or use keys from different organizations