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

Annotations already provide idempotentHint=true, destructiveHint=false, and readOnlyHint=false, so the agent knows the safety profile. The description adds useful context: it targets an existing submission ('previously reported') and identifies it via 'its token,' which goes beyond what annotations or the schema convey.

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 sentence with no filler, front-loading the action and resource before enumerating statuses and the token requirement. Every part 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 simple mutation tool, the description covers the precondition, the allowed status values, and the identifier. An output schema exists for return values and annotations cover idempotency and non-destructiveness. Only minor details like where the token comes from and when decided_on is needed are left implicit.

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 only 33%, so the description must partially compensate for undocumented parameters. It clarifies that token is the identifier for the submission, but does not explain token provenance or when decided_on is applicable. The status enum is already fully defined in the schema.

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 ('Mark'), the resource ('previously reported submission'), and enumerates the four valid statuses. The phrase 'previously reported' distinguishes it clearly from the sibling report_submission, so an agent can tell them apart without inspecting the 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 implies a prerequisite (the submission must have been reported first) but does not explicitly name alternatives or state when not to use this tool. Usage context is present but only implicit.

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