singapore_reverse_geocode

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

Annotations already declare readOnly, idempotent, non-destructive and openWorld, so the safety profile is covered. The description adds the genuinely useful auth prerequisite ('Requires ONEMAP_TOKEN') and the upstream source (OneMap), but says nothing about how many addresses come back, how radius affects results, or rate limits on the OneMap API.

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?

Two short sentences, zero filler, with the core operation front-loaded and the prerequisite second. Nothing repeats the tool name and nothing is padding.

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 and annotations carry the safety profile, so the description needn't explain return values. Still, for a 3-parameter geo tool with zero schema descriptions, leaving radius_m entirely unexplained is a real gap — an agent cannot tell whether rainfall-style proximity tuning is expected.

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 0%, so the description must compensate. It does confirm the coordinate system as WGS84 (valuable, since the schema only gives numeric min/max) and implies proximity via 'nearby addresses', but never mentions radius_m, its default of 100 m, or the 1–500 m range — a full third of the parameters is undocumented everywhere.

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 ('reverse geocoding') and resource ('WGS84 coordinates to nearby addresses') with a clear geographic scope (Singapore, OneMap). The 'reverse' qualifier implicitly separates it from forward-geocoding siblings like singapore_search_address and singapore_convert_coordinates, though it never names them.

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 only guidance is 'Requires ONEMAP_TOKEN'. There is no statement of when to pick this over singapore_search_address (forward lookup), singapore_convert_coordinates, or singapore_find_nearby_facilities, all of which plausibly overlap.

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