Open Heatmap chart app

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

Annotations declare readOnlyHint=true, indicating a safe read operation. The description adds context that data can hold rows, tree, or nodes/links, which goes beyond the annotation. There is no mention of destructive actions or other behavioral traits, but the description does not contradict annotations.

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?

The description is two sentences, front-loaded with the main purpose, and contains no redundant information. Every sentence adds value.

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?

Given the tool's complexity (7 parameters, nested objects, no output schema), the description is somewhat brief but the schema is rich and covers all parameters. The tool opens an app, so return values may be minimal. Missing a bit of context on how data maps to the heatmap, but schema compensates.

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 100%; every parameter and nested property has a description in the schema. The tool description adds a brief summary ('Use top-level title/subtitle; data holds rows, tree, or nodes/links; encoding maps fields') but does not provide additional meaning beyond what the schema already offers. Baseline of 3 is appropriate.

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 opens a heatmap MCP app for matrix intensity and two-dimensional density data. The verb 'open' and resource 'heatmap MCP App' are specific, and the description distinguishes this from sibling tools which are for other chart types (bar, line, scatter, etc.).

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 description implies usage for heatmap data but does not explicitly state when to use this tool over alternatives like scatter for density. No when-not-to-use or exclusions are provided. Sibling tool names help differentiate, but the description lacks direct guidance.

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