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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the agent knows this is a safe, non-mutating read. The description adds that the operation is the retrieval half of an async pair, but says nothing about whether the result persists, how long it is available, or how to detect completion.

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?

Two short sentences, front-loaded with the action and followed by the single required input. Efficient, with only slight redundancy against the schema's own parameter description.

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 one-parameter read tool with no output schema, the description covers what the tool returns (the explanation result) and where the input comes from. The main omission is any hint about the shape of the returned explanation or how to tell a still-running state from a finished one.

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 100% and there is only one parameter, so the schema already fully documents analysis_id. The description only restates that the id comes from explain_document, adding no format or syntax detail beyond the structured field. Baseline 3 applies.

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 (fetches) and resource (the result of an explain_document call), and ties it directly to the sibling explain_document by naming the analysis_id it returns. It does not explicitly say it is also used for completed explanations, which the title implies, leaving a small ambiguity.

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?

Gives clear context: use it after an explain_document call that was still running, passing the analysis_id it returned. It does not spell out the polling pattern (call repeatedly until complete) or when to stop, which is a minor gap for an async-result fetch.

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