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overlay_layers

Idempotent

Perform set-theoretic overlay of two geospatial layers: intersection, union, identity, symmetric difference, or difference, with automatic CRS reprojection and a provenance manifest.

Instructions

Set-theoretic overlay of two layers: intersection (default), union, identity, symmetric_difference or difference.

The overlay layer is reprojected to the input CRS when they differ; the decision is recorded in the provenance manifest. Overlay pieces of lower dimension than the inputs (shared edges, corner contacts) are dropped, and the manifest says so. Inputs without a CRS are refused; an empty result comes back with a warnings entry, never as a silent success.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "input_path": "<input_path>",
      "overlay_path": "<overlay_path>",
      "output_path": "<output_path>"
    },
    "name": "overlay_layers"
  }
}

Input Schema

Name	Required	Default
`how`	No	intersection
`input_path`	Yes
`output_path`	Yes
`overlay_path`	Yes

Output Schema

Name	Required	Description	Default
No arguments

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.3.0Aug 29, 2026

TDQS

A4.7/5.0

Behavior5/5

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

The description discloses important behaviors beyond the annotations: reprojection and provenance recording, dropping lower-dimensional pieces, refusing inputs without CRS, and reporting empty results with warnings. This is exactly the kind of contextual side-effect information an agent needs, and it does not contradict the annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is front-loaded with the core operation and each subsequent sentence adds a distinct behavioral detail without redundancy or fluff. It is compact yet information-dense.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a 4-parameter tool with an output schema, the description covers the operation variants, CRS mismatch behavior, geometric dimension handling, validation failures, and empty-result warnings. Nothing essential for selecting or invoking the tool is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

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, and it does: it explains the 'how' values and clarifies the roles of input and overlay layers. It doesn't explicitly document the path parameters, but their names are self-explanatory and the behavior around the overlay result is conveyed.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description states a specific operation ('Set-theoretic overlay of two layers') and enumerates the allowed variants, so an agent immediately knows what the tool does. This distinguishes it from siblings like clip_layer or merge_layers because it names the exact set-theoretic semantics.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description gives clear context for when the tool applies, including CRS handling and edge cases, but it does not explicitly name alternatives or say when not to use it. The set-theoretic operation definition is enough to imply the main use case.

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