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

With readOnlyHint/idempotentHint already present, the description still adds substantial non-obvious behavior: it does not advance the unread cursor, does not consume the offer, bytes are excluded from the result, and filenames remain plaintext on sealed Spaces because the server can read names. It also flags that the copy endpoint requires write scope.

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?

Front-loaded with purpose and return shape, then behavior notes, then the REST path. It is dense but nearly every clause carries information; "Idempotent" and the REST path slightly repeat what annotations/name already convey.

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?

No output schema exists, so listing the returned fields is appropriate and mostly complete. Minor ambiguity: "bytes" is listed among returned fields while a later sentence says "Bytes stay off this result," which a reader must infer means byte size vs. content.

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?

The tool takes zero parameters, so the baseline is 4; there is no parameter semantics to add. The description correctly signals the absence of filters by scoping implicitly to the current Space.

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 ("List live file offers in this Space") and immediately enumerates the returned fields (id, filename, bytes, hash). It is clearly distinguishable from get_file, which it explicitly says consumes the offer, and from other list_* siblings by scoping to file offers.

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?

It names the alternative behavior explicitly: get_file consumes, this call does not, and it routes byte-peeking to GET /v1/files/{id}/copy. What's missing is an explicit "use this when / use get_file when" statement, so the selection logic is inferable rather than spelled out.

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