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

Annotations already declare readOnlyHint=true and idempotentHint=true, so the description need not repeat safety traits. It adds valuable behavioral context: the status transition from 'waiting' to 'done', the 24-hour validity of the media_url, and the fields returned (kind, size, content type). This goes beyond the annotations and helps the agent understand expected behavior.

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 description is a single sentence that packs relevant details: the purpose, the statuses, and the returned fields. It is front-loaded with the main purpose and includes necessary specifics without fluff. It is somewhat dense but remains readable and efficient.

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?

Given the simple single-parameter tool with no output schema, the description fully explains what the agent should expect: the possible statuses and the fields returned when done. It also mentions the URL validity period, which is useful. It does not cover error conditions, but that is not critical for this straightforward operation. The description is complete enough for correct invocation.

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 100% (the upload_id parameter has a description stating it is the ID returned with the upload link). The description reinforces this by saying 'by upload_id' and mentioning the upload link, but adds little new meaning. Since the schema already documents the parameter adequately, a baseline score of 3 is appropriate.

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 clearly states the tool's purpose: it returns the status of a file uploaded via a PostWire upload link, identified by upload_id. It specifies the verb, resource, and how the resource is identified. It also differentiates from siblings like create_upload_link (which creates the link) and get_post_status (which checks post status) by focusing on file upload status.

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 gives clear context: it is used after obtaining an upload_id from an upload link. It explains the polling behavior (waiting vs done) which implies when to call it. However, it does not explicitly state when NOT to use it or compare it to alternatives, though the context is strong enough for an agent to infer its usage.

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