Find Alternative Facilities

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is clear. The description adds valuable behavior context: it returns 'ranked alternatives, each with similarity_score, match_reasons, and key_differences' and notes that it 'DISCOVERS candidates from a single seed facility.' No contradiction with annotations. Minor deduction because it doesn't explain how the ranking is computed or any rate limits, but the added return structure is helpful.

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 compact but information-dense: it opens with the use case, provides an example, lists parameters, describes returns, and gives exclusions in about four sentences. It is well-structured and front-loaded with the most important usage cue. It could be trimmed slightly, but every sentence carries meaningful guidance, so no wasted words.

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?

Given the output schema exists, the description does well to describe the return shape and use cases. However, the parameter errors (capacity_mw, name, required) make it incomplete for correct invocation. It also doesn't mention that 'match_on' and 'exclude_operator' are available for refinement. These gaps keep it from being fully contextual.

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?

The schema covers all 5 parameters with descriptions, but the description text misrepresents the parameter set. It says 'Params: facility_id or name (the target, required); optional capacity_mw, radius_km, limit,' yet the schema has no 'name' or 'capacity_mw' fields, and lists none as required. It also omits 'match_on' and 'exclude_operator.' This introduces potential confusion and could lead to incorrect invocations. The inaccuracies reduce the value below the schema's baseline coverage.

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: 'Use when a user likes ONE specific facility and wants similar nearby options to consider instead.' It gives a concrete example and explicitly distinguishes from siblings like score_facility and compare_sites. The verb 'find' and resource 'alternatives' are specific and unambiguous.

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?

Explicit usage guidance is provided: 'Use when a user likes ONE specific facility...' It also gives direct do-not-use exclusions with named alternatives: 'Do NOT use to score one site (use score_facility or analyze_site) or to compare a known short-list head-to-head (use compare_sites).' This leaves no doubt about when to invoke this tool versus siblings.

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