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

Annotations declare idempotentHint=true and readOnlyHint=false; the description enriches this by detailing JWT format, non-expiring vs. session-only semantics, the exact Authorization Bearer header format, and browser-flow behavior—none of which appear in the structured fields. This materially improves an agent's ability to invoke correctly.

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?

A single well-packed paragraph where each clause earns its place—no filler. Slight deduction for dense, meandering sentence structure that could be broken into two or three sentences for scannability, but overall efficient.

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 single-optional-param tool with no output schema and no nested objects, the description is complete: it covers the primary use case, an alternative permanent auth path, argument format, and default behavior. No critical operating detail is left unspecified.

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?

With 0% schema description coverage, the burden falls entirely on the description. It fully compensates by explaining the optional 'token' parameter as a pasted JWT for session login and clarifying the no-args call returns the auth link. This transforms the bare schema string into an actionable contract.

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 specific verbs (log in, copy access token, paste) and clearly identifies the resource (MCP.AI for IDE agents). It distinguishes itself from sibling 'connect' by focusing on credential exchange and session management, making the auth-specific purpose 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?

Explicitly contrasts two usage modes—permanent config-based login via header versus session-only pasted token—and specifies no-args behavior for the link. It stops short of explicitly naming alternatives or stating 'don't use this if…', but the guides are actionable and contextually clear.

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