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

Annotations already declare readOnly, idempotent, openWorld and non-destructive, so the safety profile is covered. The description adds value by disclosing what the call returns (title, issuer, ISIN/LEI, timestamp, PDF URL), which matters because no output schema exists. It stops short of noting error behavior for a missing/invalid 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?

Two tight sentences, zero filler, front-loaded with the action and the identity/format of the key argument before the return description.

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 output schema, the description supplies the missing return shape (fields plus the PDF URL) and the id's provenance, so an agent has everything needed to call and interpret this tool.

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 coverage is 100% with a single already-documented id parameter plus an example, so the schema carries the load. The description adds provenance for that id (it comes from amf_search_filings results), which is mildly useful but does not go beyond format details the schema provides.

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 (fetch) and resource (single French AMF disclosure), names the id field (uin_idt_uin) and its format, and explicitly distinguishes itself from the sibling amf_search_filings by casting this as the single-record follow-up. An agent can tell the two apart without opening either 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?

Makes the usage context explicit — call this after amf_search_filings, using an id taken from its results — which is the natural workflow. It does not state when NOT to use it (e.g. bulk retrieval), so it falls short of a 5.

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