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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), yet the description adds substantial context: what is never returned or stored (server names, package names, arguments, env and header values), that analysis is static with nothing fetched or run, and the exact verdict set it can return. That is exactly the value-add beyond structured fields the dimension rewards.

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?

Dense and front-loaded, leading with the check and its accepted inputs before the privacy and verdict details. A few clauses are packed tightly with semicolons, but every sentence carries information an agent needs.

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?

No output schema exists, and the description compensates by naming the verdict values and mentioning the pinning advice and permalink that come back. Combined with the two-parameter schema and full annotation coverage, nothing essential 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 coverage is 100%, so the baseline is 3. The description goes beyond the schema by enumerating the recognized config filenames (.mcp.json, claude_desktop_config.json, mcp.json, config.toml) and by framing the text parameter around pasted config content, which helps the agent pick the right filename value.

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?

States a specific verb and resource ('Check a pasted MCP client config') and enumerates the concrete file types it accepts (.mcp.json, claude_desktop_config.json, mcp.json, Codex config.toml). This clearly separates it from scan_package, which deals with packages rather than config text.

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?

Gives clear usage context: paste config text, remove secrets first, and it is static-only so nothing is run or fetched. It does not explicitly name scan_package or lookup_verdict as alternatives or state when to prefer them, so it stops short of full routing guidance.

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