her_nearby

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

With no annotations provided, the description carries the full burden of disclosing behavior. It reveals key constraints (NHLE-only, coordinate system exclusivity), output ordering (sorted by distance), and result fields (distance_m, bearing_deg), which go beyond the basic search semantics.

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 well-structured with clear sections (NOTE, Args, Returns, Tips) and front-loads the primary purpose. Despite its length, every sentence adds value, and the 'Tips for LLMs' section is practical without being redundant.

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 has no annotations or output schema, so the description must provide complete context. It covers purpose, scope, parameters, output structure, and usage caveats, including recommendations for complementary tools – making it adequately complete for effective tool selection and invocation.

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 provides only type and default for each parameter, so the description's Args section is essential. It explains coordinate systems (WGS84, BNG), pairing requirements (lat with lon, easting with northing), and output_mode options, fully compensating for the 0% schema 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 opens with a concrete verb phrase 'Find NHLE heritage assets near a single point' and then elaborates on scope (England only) and output (sorted by distance). It clearly distinguishes itself from sibling tools by explicitly noting the NHLE-only scope and directing to Scottish and aerial alternatives.

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?

It directly states when to use this tool and when not, with a dedicated NOTE listing alternative tools for Scotland and aerial features. The Tips section even recommends combining this with other searches for comprehensive results, giving clear context.

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