Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations cover the safety profile (readOnlyHint=false, destructiveHint=false, idempotentHint=false), and the description adds real context beyond them: it 'may store the generated script', 'reports failed/skipped steps', runs on server OHLCV in-sample, and consumes the shared public Monte Carlo pool with quota implications. These are meaningful behavioral traits not derivable from annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Dense but front-loaded: the pipeline and the minimum-trades gate come early, and the alternative routing sentence closes it cleanly. The opening 'THE PUBLIC PLAY BUTTON' is the one non-earning phrase.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

An output schema exists, so return values need not be explained; the description still covers execution context, the engine, and partial-failure behavior. Given a 4-param, no-nested-object tool, it is close to complete, with only parameter nuance left unaddressed.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 75%, so the schema already documents idea, asset and timeframe. The description adds no parameter-level meaning (defaults, formats, style semantics), so it does not compensate for the partially undocumented 'style' parameter. Baseline 3 is appropriate.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description names a concrete pipeline (generate ArenaScript, validate, backtest, run Monte Carlo) and marks its scope as 'public' vs the sealed-holdout path, so an agent can tell it apart from get_lab_desktop_handoff. It is less sharply differentiated from close siblings like invent_and_backtest or the standalone generate/backtest/monte_carlo tools, and the 'THE PUBLIC PLAY BUTTON' framing is marketing rather than descriptive.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

It gives an explicit precondition ('when there are at least ten trades') and an explicit when-not with a named alternative ('For sealed holdout science, use get_lab_desktop_handoff'). It stops short of routing between this all-in-one pipeline and the individual generate/backtest/Monte Carlo siblings.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.