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

Annotations already declare readOnly/idempotent/non-destructive and the description is consistent with them, while adding context the annotations cannot carry: 404 semantics when nothing was stored, the R2 backing store, and that visibility matches the listing page. This is real behavioral value beyond structured fields.

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 condition is front-loaded, but the same rule is stated twice ('Only when get_listing carries readme_api; 404 when none was stored' and again in the final sentence), which is redundant padding rather than earning 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 read tool, the description covers storage location, visibility model, and error behavior, which is nearly everything an agent needs. Only the separation between the required `id` and the auth/retry parameters is left entirely to the schema.

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%, so the baseline is 3 and the schema already documents `id`, `api_pass`, and `retry_key`. The description only implicitly references the listing id and adds no syntax or format detail for the three parameters.

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+resource combination (retrieve the README collected for a listing) and names the storage location (R2, bucket `mural-coleta`). It also distinguishes itself from the get_listing sibling by making the README's existence conditional on that listing carrying `readme_api`.

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?

Explicitly states when to call it ('only when the listing page carries `readme_api`') and what happens otherwise (404, no README collected). It also rules out a false assumption by noting it does not fetch GitHub. Routing relative to get_listing is unambiguous.

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