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

The annotations include readOnlyHint:true, which already signals a safe read operation. The description adds that it returns 'full published details' and that the name parameter accepts partial matches. It does not disclose behavior for ambiguous partial names (e.g., multiple matches) or what happens if the facility is not found, which would be useful additional context.

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?

The description is a single sentence of 17 words, front-loaded with the core function ('Full published details for one facility') followed by the two identification methods. No filler or redundant information.

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?

The tool is simple with an output schema present, so return values are already defined. However, the description does not address important edge cases: what happens if both id and name are provided, or if a partial name matches multiple facilities. These are clear gaps in guidance for an agent, making the description adequate but not fully complete.

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%, meaning both parameters are described in the schema ('Numeric facility id' and 'Facility name, partial match accepted'). The description adds the source hint that id comes from search_facilities, which is a small extra but not substantial. Thus, the description does not significantly expand on the 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 description clearly states the tool's purpose: retrieving 'Full published details for one facility'. The verb 'get' and resource 'facility' are explicit. It also distinguishes itself from siblings like search_facilities by specifying it returns a single facility, identified by id or name.

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 provides clear usage context: 'by numeric id (from search_facilities)' suggests obtaining an id from the search tool first, and 'or by (partial) facility name' offers an alternative entry point. This gives the agent a clear sense of when to use this tool relative to search_facilities, though it does not explicitly state when not to use it.

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