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

Annotations already declare readOnlyHint, idempotentHint and openWorldHint=false, so safety is covered; the description's contribution is disclosing the shape of the returned data (per-fact evidence status, source ids, checked dates, missing information), which is genuinely useful since there is no output schema. It still omits likely-failure behavior (unknown or malformed slug) and any notion that no filtering/pagination applies.

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?

It is a single compact sentence with no filler, which is good, but it is a fragment with no verb, so it is under-specified rather than truly concise. Restructuring around a main verb would cost little space and add clarity.

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 no output schema, the description partially compensates by enumerating the profile's components, which is the most valuable thing it could add. It is nevertheless incomplete as a tool definition because the retrieval action and the slug parameter go unstated.

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 required parameter, slug, is never mentioned in the description. The description does not explain that the slug identifies a supplier, nor that it can be obtained from search_suppliers, so it adds no meaning over the bare schema.

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 text is a noun phrase describing the resource's contents ('A supplier profile: facts with per-fact evidence status...') rather than stating the action. It does differentiate the resource from list/search siblings by enumerating what a profile contains, but it never says what the tool does to a slug, so an agent must infer 'retrieve a supplier by slug'.

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?

No when-to-use guidance, no prerequisites, and no mention of the obvious alternative, search_suppliers, despite it being a sibling. The agent gets no help deciding between fetching a profile by slug and searching.

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