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

Annotations already mark the tool as read-only and not open-world, so the safety profile is covered. The description adds useful behavioral context: the data is hourly snapshots, grouped by bookmaker, and the tool is the most expensive at 25 cr. This goes beyond what annotations provide.

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?

Two sentences with no wasted words. The core purpose is front-loaded, followed by cost and a clear alternative. Every sentence earns its place.

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?

With an output schema present, read-only annotations, only one required parameter, and a clear description of the data granularity and cost, the definition is complete for an agent to invoke correctly. The alternative tool is also named for simpler use cases.

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 100%, so the schema already documents game_id and bookmaker. The description adds that snapshots are grouped by bookmaker, which clarifies the bookmaker parameter's role, but it does not add significant new parameter-level detail beyond the schema.

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 states a specific verb and resource: seeing how a game's lines moved via the full time series of hourly snapshots grouped by bookmaker. It clearly distinguishes itself from get_odds, so an agent can tell which tool to choose.

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 description explicitly says when to use this tool versus the cheaper alternative get_odds, naming the exact condition ('if you only need opening, closing, or current lines'). It also provides cost context, making the trade-off obvious.

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