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

With no annotations, the description carries the full burden and does so: it declares the auth requirement and format (Authorization: Bearer cf_…), where to obtain a token, the ownership scoping rule, and the read-only/non-mutating behavior ('never runs a new audit'). It also sketches the returned judgment scale (tier T0 to T5), which is exactly the behavioral context missing from 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?

Four sentences, all of which carry information: auth, purpose, ownership scope, and the no-new-audit constraint. The only structural nit is that the opening sentence is an auth preamble, so the actual purpose arrives in the second sentence rather than being front-loaded, which slightly weakens scanability.

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 single-parameter read tool with no annotations and no output schema, the description supplies everything an agent needs: credentials, prerequisite ordering, ownership limitation, and even the shape of the result (a T0–T5 tier) so the return value needn't be documented separately. Nothing material 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 100% and there is only one parameter, so the schema already explains that 'scan' is the public id from a citefiles.com/report/<id> URL. The description corroborates the source of that id ('run it from the scan's report page first') but adds no syntax or format detail beyond the schema, making the baseline 3 correct here.

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 and resource: 'Read the stored Agent Commerce Readiness audit for a scan on your citefiles account', and it scopes the content of that audit (agent auth, API discovery, text-readable prices, machine-payable challenge, tier T0–T5). It also explicitly separates itself from the scan-running sibling by stating 'This tool never runs a new audit', so an agent can tell it apart from citefiles_scan without opening a 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?

It gives a clear precondition and ordering: run the audit from the scan's report page first, then call this tool, and it notes the account-ownership restriction ('Only returns audits for scans your account owns'). What it lacks is explicit routing to an alternative when a scan has no audit yet — it implies raising the audit first but never names the tool that does it.

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