Total length in metres of a polyline through 2+ coordinates, summed geodesically. This measures the line you supply, NOT a driven route — use route for that. Local computation: no network call, no quota.
| Name | Required | Description | Default |
|---|---|---|---|
| points | Yes | The coordinates to consider. |
| Name | Required | Description | Default |
|---|---|---|---|
| length_m | Yes | Total geodesic length in metres. |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries the full behavioral burden. It discloses that the computation is local ('no network call, no quota') and that the measurement is geodesic and summed over a 2+ point polyline. It does not detail error behavior for fewer than 2 points, but for a simple calculation tool this is adequate context.
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?
Three short sentences with no filler. The core measurement is front-loaded, the route distinction follows, and the local-computation note is compact and useful. Every sentence earns its place.
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?
For a one-parameter tool with an output schema, the description covers the essential context: units (metres), geodesic method, line-vs-route distinction, and the side-effect-free local computation. Nothing critical is missing for selecting and invoking it 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?
The schema provides 100% coverage for the `points` parameter but only says 'The coordinates to consider.' The description adds meaningful semantics: a polyline must have 2+ coordinates and the calculation is geodesic and summed. This goes beyond the schema's bare description.
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 computes 'Total length in metres of a polyline through 2+ coordinates, summed geodesically', specifying both the resource (a supplied polyline) and the operation (length measurement). It also explicitly distinguishes itself from a driven route by pointing to the `route` sibling tool, eliminating ambiguity.
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 provides explicit guidance: 'This measures the line you supply, NOT a driven route — use `route` for that.' This tells an agent exactly when to use this tool versus the alternative sibling, making the selection criterion clear.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.
Most tools target a distinct action and resource pair, and descriptions are explicit about which tool fits which scenario. The closest overlaps—plan_ev_route vs cheapest_charging_along_route, and route vs plan_day vs order_stops vs optimise_routes—are mitigated by clear guidance, so an agent can usually pick correctly.
Tool names overwhelmingly follow a verb_noun snake_case pattern (plan_ev_route, set_palette, list_style_layers) with a consistent geo_ prefix for geometry helpers. Minor deviations like elevation, route, and matrix are short and readable but break the strict verb_noun convention.
At 39 tools, this surface is well past the 25+ threshold and feels heavy even for a broad mapping platform. The set spans routing, geocoding, places, styles, EV/fuel, telematics, usage, and feedback, which would be easier for an agent to navigate if split into smaller domain-focused servers.
For the stated breadth, coverage is strong: routing, multi-stop planning, VRP, EV/fuel detours, geocoding, places, geometry, style lifecycle, and telematics all have workable primary paths. Minor gaps like no style deletion, no route alternatives, and no batch geocoding are present but do not create dead ends for core workflows.