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

Annotations already declare readOnlyHint=false and destructiveHint=false, but the description adds genuinely new behavior: an in-flight diagnostic may still complete and consume one credit within the original cap, and terminal results stay readable until retention expires. That credit-charging caveat and the retention guarantee are exactly the kind of side-effect detail annotations cannot express, and they are consistent with destructiveHint=false. Minor gap: no error or auth failure behavior described.

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?

Four short clauses with no filler, and the action is front-loaded before the cost and retention caveats. The semicolon-joined fragments ('confirm=true required; terminal results remain readable...') are slightly compressed but still readable.

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?

An output schema exists, so return values need not be explained, and the description covers the two things an agent most needs before a mutation: the credit side effect and the confirmation gate. It stops short of the api_key/auth expectation and what happens when the job is already terminal.

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%, so the description must carry the load; it does clarify the critical piece — 'confirm=true required' — which explains why a boolean with default false gates the operation. But job_id and the unusual api_key parameter are left entirely undefined, and the description's 'required' framing is in tension with a schema that lists only job_id and api_key as required.

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 your readiness/callback job'), which maps clearly onto the sibling read_readiness_jobs without ambiguity. It does not explicitly name that sibling or any alternative, so differentiation is implied rather than stated.

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?

Usage is implied by the imperative 'Cancel your ... job' and reinforced by 'No further checks start', which tells the agent the effect of invoking it. However, there is no explicit when-to-use vs when-not guidance and no mention of alternatives such as delete_diagnostic_watch or how to check job state first.

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