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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is free. The description adds value beyond that by clarifying the return payload is the full document text (as opposed to search snippets) and that ids must be sourced from search. It does not describe what happens for an unknown or stale id, which is the main remaining gap.

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?

One sentence, front-loaded with the verb and resource, with the id-provenance constraint folded in without filler. Nothing to cut.

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 one-parameter read tool with no output schema, the description covers purpose, input provenance, and the nature of the return value. Missing only edge-case behavior (unknown id, very large documents or truncation), which is minor at this complexity.

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% and the schema already gives the id format example (tool:calc_cam_reconciliation). The description still adds meaning by tying id provenance to search, which discourages fabricated identifiers — a real constraint rather than a restatement.

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), a specific resource (full text of a FactLot knowledge document), and the keying mechanism (by id). The phrase 'id returned from search' cleanly separates it from the sibling search tool that produces those ids.

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?

The description establishes the prerequisite workflow: ids come from search, so an agent knows to call search first rather than inventing an id. There is no explicit statement of when not to use it, but with a single clear retrieval purpose and no competing sibling (search returns matches, this returns full text), the guidance is sufficient.

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