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

Annotations declare readOnlyHint=true, so the tool is known to be read-only. The description adds meaningful behavioral context: it returns 'ranked loc_id matches with bridge vintage, overlap weights, and provenance where applicable,' and notes 'No payment required,' which goes beyond the annotation. It does not disclose limitations like rate limits or error handling, but the annotation covers the safety profile.

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 extremely concise—two sentences—and front-loads the core purpose with a clear verb and resource. The examples are packed into the first sentence without wasting words, and the second sentence covers output and cost. Every sentence earns its place; there is no fluff.

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?

Despite having 13 parameters and no output schema, the description adequately covers the tool's purpose, input format, and output nature ('ranked loc_id matches with bridge vintage, overlap weights, and provenance'). It does not explain the interaction between parameters (e.g., when to use items vs value), but the schema's anyOf and parameter descriptions handle that. The description is sufficient for an agent to understand what to call and what to expect.

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%, so the schema already documents all 13 parameters with detailed descriptions. The description adds value by providing concrete examples of from_system and value pairs (e.g., 'zip'='00601'), which illustrate the expected format and are not in the schema itself. This extra context justifies a score above the baseline of 3.

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 a specific verb ('converts'), a precise resource ('external or adjacent geographic reference system into the DaedalMap loc_id universe'), and provides concrete examples ('zip' value='00601', 'nws_fire' value='AKZ317', 'admin_boundary' value='Fairfax County'). This makes the tool's function unambiguous and distinguishes it from sibling conversion tools like convert_reference.

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 gives usage examples but does not explicitly state when to use this tool over its siblings, such as convert_reference. There is no 'when to use' or 'when not to use' guidance, no mention of exclusions, and no alternative tools are referenced. The examples imply usage, but the guidance is only implicit.

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