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

Annotations already declare destructiveHint=true, idempotentHint=false, and readOnlyHint=false, so the safety profile is covered. The description adds genuinely non-structured context: permanence, the valid source states (ACTIVE or PAUSED), the target state (CANCELLED), and the irreversibility contrast with pause/resume.

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?

A single dense sentence with zero filler; the terminal/permanent nature is front-loaded and the alternative is attached as a contrast clause rather than a separate sentence.

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 two-parameter destructive mutation with no output schema, the description covers the critical decision facts: state preconditions and irreversibility. It leaves the reason parameter and any response/error behavior unexplained, but nothing else an agent needs to invoke it correctly is missing.

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 0% and neither parameter is described in the schema, so the description carries the full burden. It mentions the match implicitly but says nothing about matchId format/expectations or what the reason parameter is for or its length limit.

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 (cancel/pause a match), names the resulting terminal state (CANCELLED), and explicitly positions itself against pause_match/resume_match. An agent can distinguish it from sibling lifecycle tools without opening any 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?

Names the alternative (pause_match, with resume_match) and the condition that distinguishes it: this action is not reversible. That gives an agent the key routing decision, though it doesn't state preconditions such as required permissions or which roles may cancel a match.

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