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

Annotations cover read-only and open-world traits. Beyond that, the description discloses data provenance (OpenStreetMap, ODbL), a result cap (50), the exact returned fields when tagged, and an unusual pricing/auth model ($0.002 USDC via x402 on Base/Solana/Arc, failed calls free). That pricing detail is genuinely non-obvious and valuable.

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?

Front-loaded with the core purpose, then progressively adds source, output fields, and pricing. Dense but information-bearing; the pricing sentence is slightly verbose yet earns its place as it affects whether an agent should call at all.

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?

An output schema exists, yet the description still summarizes returned fields (name, distance, address, hours, phone, website), which is a bonus. Combined with source, limits, and cost, an agent has everything needed to invoke this correctly.

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 description coverage is 100%, so every parameter is already documented (including default values and ranges). The description's 'within up to 5 km' mirrors the radius cap and the category list mirrors the enum, adding little beyond the schema. Baseline 3 is appropriate.

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?

States a specific verb+resource ('Points of interest near a point') with explicit scope (up to 5 km), two input modes (lat/lon or geocoded place name), and an enumerated category list. An agent can instantly distinguish this from geocode, distance, or address_parse siblings.

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 context is implied through the input description (lat/lon vs place name) but there is no explicit when-to-use/when-not guidance and no alternative routing. Given nearby siblings like geocode and us_geocode, an explicit 'use X to resolve an address first' would have added real value.

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