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

Annotations already declare readOnly/openWorld/non-destructive, so the safety bar is covered; the description adds meaningful behavior of its own by disclosing that the event log is capped at 100 events and by laying out the shape of the returned data (match, players, ordered events). What's missing is any note on error behavior for an invalid or stale match_id.

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?

One front-loaded sentence that names the resource first, then walks through the three return groupings in reading order, followed by a short flag about the event cap. No filler and no repetition of annotation content.

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 a single integer parameter, no output schema, and annotations covering the safety profile, the description does the remaining work well: it explains both how to obtain the id and what the response contains, including the one non-obvious constraint (100-event cap). Nothing an agent needs to invoke it correctly is absent.

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?

There is a single parameter at 100% schema description coverage, and the description's mention of match_id repeats the schema text almost verbatim. The baseline of 3 applies since the schema already carries the parameter meaning and the description adds no format or validation nuance beyond it.

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?

States a specific verb ('Show') and resource ('one match in detail') and enumerates exactly what is returned: match version/time/attributes, per-player attributes and characters, and the ordered event log. It clearly occupies the detail-view niche relative to list_recent_matches, so an agent can distinguish it from siblings without opening a schema.

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 tells the agent where the required input comes from ('match_id is the id from list_recent_matches'), which implicitly routes the agent to the list tool first and to this tool for single-match detail. It stops short of an explicit when-not-to-use statement, but the workflow context is clear.

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