| name | arena |
| description | Invoke the `arena` CLI for the Lex finance arena. Commands: episodes, verify. Use to list trading scenarios and to replay-verify a recorded trail and recompute its authoritative outcome. |
| when_to_use | When you have a recorded finance-arena trail (JSONL) and need a trustworthy verdict — the outcome is recomputed by replaying the trail through the episode's deterministic rules, never trusted from a client. |
arena
Auto-generated skill file for arena v0.1.0
Re-generate with: arena skill
The Lex finance arena. A submission is a trail, not a score: verify replays
the recorded steps through the episode's deterministic rules and recomputes the
authoritative outcome — no LLM, no network — so a leaderboard built on its output
can't be faked.
Only the deterministic, read-only commands are exposed as agent tools here.
Running an agent against an episode (arena run), uploading results
(arena submit/publish), and authenticating (arena login) remain
human-driven CLI commands — they spawn external programs or use stored
credentials, which don't belong on an unattended tool surface.
Available commands
arena episodes — list the available episodes (scenarios). (idempotent)arena verify --episode <id> <trail.jsonl> — replay a trail, recompute the outcome. (idempotent)
arena episodes
List the available arena episodes (scenarios). Prints JSON.
arena verify
Replay a recorded trail through the episode's deterministic rules and recompute
the authoritative outcome. Prints a JSON verdict to stdout.
Arguments
episode (string, -e/--episode) — episode id, e.g. ep1-baseline.trail (string, positional, required) — path to the trail JSONL file.
Example
arena verify --episode ep1-baseline ./trail.jsonl
Output format
Both commands emit JSON to stdout (the trailing exit-code line lex run prints is
stripped by the launcher).
Exit codes
| Code | Meaning | Action |
|---|
| 0 | Success / verified | Proceed |
| 1 | Trail rejected (tampered or illegal step) | Do not trust the submission |
| 2 | Invalid arguments | Correct and retry |
Further discovery
arena help — usage for all commands (including the human-only ones)arena introspect — machine-readable command tree (JSON)
As MCP tools
Run this CLI as MCP tools via acli-mcp:
ACLI_BIN=arena python -m acli_mcp
Or reach the agent's execute_trade_goal capability directly over MCP — the
A2A+MCP server (examples/a2a_agent.lex) exposes it at POST /mcp.
