retrieve_file

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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=true, so the safety and repeat-call profile is fully covered structurally. The description adds only that it returns metadata (not file bytes) for a single image, which is a modest but real clarification beyond annotations; it says nothing about permission requirements or error behavior for a missing id.

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?

One sentence, front-loaded with the verb and resource and back-loaded with the identifier; there is no filler whatsoever.

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 an output schema present, return values need not be described, and annotations cover the safety profile. The remaining gap is minor: how the id is obtained and whether the tool is limited to images are left implicit, but nothing required to invoke it correctly is missing.

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 0% and the single parameter carries only a regex pattern, so the description does the naming work by stating the lookup is 'by file_id'. However, it adds no meaning beyond the parameter name — it does not explain the expected 'file-api-' prefix format or that the id comes from upload_file/list_files.

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 names a specific verb (Retrieve), a precise resource (metadata for one image), and the identifier used to select it (file_id), which separates it from the plural list_files and the mutating delete_file/upload_file siblings. It stops short of explicitly contrasting itself with list_files or stating whether non-image files are handled, so it is clear but not fully sibling-differentiated.

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?

There is no guidance on when to call this versus list_files or upload_file, no prerequisites, and no exclusions. The only implicit cue is that it fetches a single known file, which the agent must infer from the wording.

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