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

The readOnlyHint annotation already establishes this is a safe read, so the description's job is lighter. It adds genuine value by disclosing the key return content, including processing_status and the validation_report that explains rejection, which an agent would not otherwise know exists. It omits auth/permission notes and any error behavior for unknown ids, keeping it short of a 5.

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?

A single front-loaded sentence naming the resource and its notable fields, followed by the underlying REST endpoint. No filler or redundancy.

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?

There is no output schema, so the description usefully names the two payload fields an agent most needs. For a simple get-by-id tool this is nearly complete; the only gap is that it doesn't describe the full metadata shape or failure modes.

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?

Only one parameter (file_id), and schema description coverage is 100% with an example ('file-abc123') already in the schema. The description adds nothing about the parameter, so the 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 and resource ('Fetch one file's metadata') and names the distinguishing payload fields (processing_status, validation_report). An agent can tell it apart from together_list_files and together_list_fine_tune_events without opening the schema.

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?

Usage is implied: fetch a single file by id, notably to learn why a fine-tune training file was rejected. However, there is no explicit statement of when to prefer this over together_list_files or a fine-tune status call, and no prerequisites or exclusions are given.

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