qgis-dev-probe-mcp

Overview Schema Source Related Servers Discussions Admin

add_layer

Loads a local vector or raster layer into a live QGIS session from a file path, including GeoPackage sublayers via 'file.gpkg|layername=x'.

Instructions

Add a vector/raster layer from a local path (GeoPackage sublayer syntax 'file.gpkg|layername=x' works).

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": {
      "path": "<path>"
    },
    "name": "add_layer"
  }
}

Input Schema

Name	Required	Default
`kind`	No	auto
`name`	No
`path`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Oct 25, 2026

TDQS

C2.8/5.0

Behavior2/5

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

With no annotations, the description must carry the full behavioral burden. It discloses that the path is local and that GeoPackage sublayer syntax is supported, but says nothing about mutation side effects, required permissions, error handling, or what happens when the layer already exists.

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?

A single, front-loaded sentence with no wasted words; it immediately states the action and the key path syntax detail.

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

Completeness2/5

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

For a mutation tool with no annotations, no output schema, and 0% schema coverage on three parameters, the description is too thin. It should explain 'kind' and 'name' semantics, prerequisites, and side effects to be complete enough for reliable invocation.

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

Parameters2/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0%, so the description must explain all three parameters. It clarifies the 'path' parameter (local path and GeoPackage sublayer syntax) but provides no meaning for 'kind' or 'name', leaving two parameters undocumented.

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

Purpose4/5

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

The description states a specific verb ('Add') and resource ('layer') and clarifies support for vector/raster from a local path. It is clear about what the tool does but does not explicitly distinguish it from siblings like remove_layer or list_layers.

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

Usage Guidelines2/5

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

The description offers no guidance on when to use this tool versus alternatives, nor any preconditions (e.g., project must be open, path must be local). It implies usage from the phrase 'from a local path' but leaves selection criteria unstated.

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