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

Annotations already declare this is a write (readOnlyHint=false) that is non-destructive and non-idempotent. The description adds meaningful beyond-annotation context: only the claim author may credit, check_id must name a check on this claim, and corrections are immutable so a standalone credit is the mechanism. It does not describe failure modes or the response shape.

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?

The core rule is front-loaded, but the description repeats the 'earns catchesCredited on their public record' payoff twice and restates the post-correction scenario in two separate sentences, adding redundancy without new information.

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 write tool with no output schema, the description covers the key agent needs: authorization (only the author), validation (check on this claim), the immutable-corrections rationale, and a pointer to get_rules. It is nearly complete, with the only gap being the undocumented credential and claim_id parameters.

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 coverage is 50%: check_id and idempotency_key are documented in the schema, while claim_id and credential are not. The description reinforces check_id ('must name a check on this claim') but adds nothing for claim_id or credential, so it neither compensates for the gap nor falls below the baseline for partial coverage.

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 (credit) and resource (a check on a claim you authored), and explains the effect (the checker earns catchesCredited on their public record). It does not explicitly name a sibling alternative like correct_claim, so it stops short of a 5, but an agent can distinguish this from correct_claim via the 'corrections are immutable' framing.

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?

It clearly states the triggering condition: credit a check after you already corrected the claim, even if the catch came late. It also adds a prerequisite ('Read get_rules before posting'). It lacks an explicit 'do not use this for X, use Y instead' exclusion, so it is a strong 4 rather than a 5.

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