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

Annotations already mark this as read-only, idempotent, and non-destructive. The description adds substantial behavioral detail beyond that: results are returned in the same form the original call would have produced, unfinished requests return {"status": "processing"}, results are kept for 30 days, and re-reading is free. No contradiction with annotations.

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 longer than a one-liner, but every sentence carries essential information: endpoint, return-shape mapping, async collection mechanics, retention/free re-reads, and retry behavior. It is front-loaded with the endpoint and purpose, with supporting details in logical order.

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?

With no output schema, the description must explain return values, and it does: Markdown stays Markdown, structured operations are objects, screenshots are images, and scrapes become combined objects. It also covers the pending state and retention duration, so an agent has enough information to call and handle the response correctly.

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%, so the baseline is 3. The description adds meaning by explaining that the token is the async handle produced by earlier non-sync calls and that it converts that token into the final result. It also clarifies that re-reading an existing token is free, which informs how the token parameter should be treated.

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 opens with a precise verb and resource: 'Exposes GET /result/:token. Returns the result of a past request.' It immediately distinguishes this tool from sibling tools by explaining that it is the collection mechanism for async calls, turning a returned token into the corresponding result.

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 when-to-use context: 'any tool called without sync: true answers with a token, and this turns that token into the result.' It also covers the free re-read case. It does not explicitly contrast with siblings like get_request or list_requests, but the async-token trigger is a strong usage signal.

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