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

Annotations already establish the full safety profile: readOnlyHint=true, idempotentHint=true, destructiveHint=false, openWorldHint=false. The description adds one useful behavioral detail — that it returns the 'full text' of a single record as opposed to a list or snippet — but says nothing about size limits, rate limits, or what happens when the id is stale or invalid.

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?

A single sentence with no filler, front-loaded with the verb and carrying four distinct pieces of information: full text, one result, from search, by id. Nothing could be removed without losing content.

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-only, non-destructive fetch with no output schema, the description covers what the agent needs to select and invoke it. The only mild gap is that 'full text' and the shape of the returned payload are left unstated, which matters little given the annotations already establish the safe-read nature of the call.

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?

There is a single parameter with 100% schema description coverage ('Id from search.'), so the schema already carries the parameter semantics and a baseline of 3 applies. The description restates the same constraint ('by id', 'from search') without adding format, validity, or sourcing detail beyond it.

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 gives a specific verb and resource: 'Fetch the full text of one result from search, by id.' That is far more informative than the bare name 'fetch'. However, it does not distinguish itself from similar-looking siblings such as get_body and get_record, which an agent could plausibly confuse for this same operation.

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?

Usage is implied rather than stated: the phrase 'one result from search' signals that this is the follow-up step after a search call, and the 'by id' phrasing implies the id must originate from that search. There is no explicit when-not guidance and no sibling (get_body, get_record, search) is named as an alternative, so the agent must infer the routing.

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