Retrieve all active canvases and their dimensions to track current pixel art projects and available workspace.
List all active canvases with their dimensions.
This tool declares no required parameters. Add optional parameters from the input schema as needed.
{
"id": 1,
"jsonrpc": "2.0",
"method": "tools/call",
"params": {
"arguments": {},
"name": "list_canvases"
}
}| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden. 'List' implies a read-only operation and 'active' scopes the result, but the description does not disclose any side effects, return structure beyond dimensions, or possible limitations like pagination or ordering.
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?
Single front-loaded sentence that states the action, scope, and output data without any filler. It is appropriately concise for a zero-parameter list tool.
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 zero-parameter read-only operation the description is largely sufficient, but with no output schema it omits identifiers or other canvas fields that an agent would need to use sibling tools like set_pixel. It also does not define what 'active' means.
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 input schema is empty (0 parameters), so there is no parameter burden to document. The baseline of 4 applies because the description does not need to clarify any parameter semantics.
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 uses a specific verb (List), a clear resource (canvases), and a scope qualifier (active), while stating the returned data (dimensions). This makes it clearly distinguishable from the sibling mutation/query tools.
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?
No explicit when-to-use or alternative guidance is provided. The usage is implied by the description's declarative statement — an agent can infer that this is for retrieving current canvases — but it does not explain when to prefer it over siblings.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.