npm_check_auth

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false. The description adds valuable behavioral context beyond this: it returns a canPublishHeadless boolean and a recommendation, detects headless limitations, and provides the exact terminal command for a human to run. It also explains the MCP server constraint (cannot open browsers), which is critical for agents.

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 concise yet complete: two short paragraphs, first sentence front-loads the purpose, subsequent sentences add necessary behavior and usage context. Every sentence earns its place with no redundancy or fluff.

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 health check, the description fully covers what it does, when to use it, what it returns (structured data, canPublishHeadless boolean, recommendation, terminal command), and why it exists (AI limitations). This is complete given the absence of an output schema.

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 tool has zero parameters, so the schema provides no semantics to add. The description correctly focuses on outputs rather than inputs. The baseline for 0 params is 4, and the description doesn't miss any parameter-related information.

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 it is a 'Quick auth health check' that returns structured data about npm auth status, token capability, and headless publishing possibility. This specific verb+resource framing distinguishes it from siblings like npm_whoami (identity only) and npm_verify_token (token verification) by focusing on pre-publish headless capability.

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 instructs 'Run this BEFORE attempting any publish operation' and explains why (AI cannot open browsers/enter OTP codes, provides terminal command for human). This is clear context, though it doesn't name specific alternative tools for when not to use it.

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