List Available Tools

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, covering the safety profile. The description adds the behavioral detail that the output is categorized and includes tags (OSS/MSI/B2B/Commerce), which enriches understanding beyond the annotations. No contradiction exists.

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?

Two sentences with zero wasted words. The first sentence states the core function, and the second provides the usage trigger. Information is front-loaded and efficiently structured.

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 simple tool with one optional parameter, an output schema, and annotations covering side effects, the description is complete. It explains what the tool returns (categorized list with tags) and when to use it. Nothing an agent needs to invoke it correctly is missing.

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% because the single 'tag' parameter has a full description in the schema ('Filter tools by edition tag. Omit for full catalog.') and a complete enum. The description itself adds no parameter-level insight, so the baseline score of 3 applies.

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 a specific verb ('Returns') and resource ('categorized catalog of all MCP tools'), and explicitly lists the tag categories. It distinguishes itself from sibling tools by being a meta-tool that catalogs other tools, which none of the siblings do. The purpose is unambiguous.

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 gives an explicit usage context: 'Use when unsure which tool fits a task.' While it doesn't explicitly state when not to use it, the guidance is clear and actionable. There are no alternative tools mentioned, but as a meta-tool, its use case is inherently distinct from the direct data-access siblings.

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