backtest_check

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

With no annotations, the description carries the transparency burden. It discloses the scanning mechanism, the two flag types (FUTURE_EVENT, LATE_REVISION), and the is_clean output. This goes beyond a basic summary, though it doesn't state read-only behavior or error conditions.

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?

Three sentences, each earning its place: purpose, mechanism, output/significance. No fluff, front-loaded with the core function.

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?

Given the simplicity (1 parameter, no output schema), the description covers the essential aspects: what it checks, what flags it returns, and what a clean result signifies. Missing edge cases or error handling, but these are less critical for this tool.

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 coverage is 100% for the single parameter. The description only references 'given simulation date' without adding detail beyond the schema's ISO-8601 UTC timestamp definition, so it meets the baseline but adds no extra semantics.

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 clearly states the tool's purpose with a specific verb ('Detect lookahead bias') and resource ('a backtest simulation'). It distinguishes itself from memory retrieval siblings by focusing on validation and analysis of memory store contents.

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?

The context is clear: it's used to produce a clean report for risk committees. It implies when to use it (when validating a backtest) but doesn't explicitly list exclusions or alternatives. Given the specialized nature, this is sufficient.

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