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

Annotations already declare destructiveHint=true and openWorldHint=false, and the description adds real context beyond them: the call opens voting, returns a vote link for the group chat, and requires organiser rights plus user confirmation. It does not clarify whether re-entry overwrites an existing result, which matters for a destructive operation.

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 short sentences, zero filler, with the core action front-loaded and the permission and confirmation caveats following in order of importance. 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?

For a three-parameter mutation with annotations covering the safety profile and no output schema, the description covers permissions, side effect (opening voting), and return value (vote link). The remaining gap is idempotency/overwrite behaviour on an existing score.

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% and all three parameters are documented in the schema, including where matchId comes from. The description adds no syntax, format, or validation detail beyond the schema, so the baseline of 3 applies.

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 and resource ('Save a match's final score'), which is distinguishable from siblings like set_game, answer_game, or get_match. It does not explicitly name an alternative tool, but the operation itself is unambiguous.

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?

Gives a clear precondition ('organisers only') and an explicit procedural directive ('Confirm the score with the user first'), which is genuinely useful for a write operation. It stops short of routing the agent away from similar tools such as set_game or answer_game.

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