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

The description goes far beyond the annotations (which only cover read-only/idempotent/open-world safety). It discloses what is flagged (unseen human publisher after 180+ days inactivity within 365 days), what is deliberately reported but not flagged (trusted publishing, pre-release, established maintainers), the ecosystem-specific capability gap, and the key limitation that it does not detect hijacked existing accounts and is a heuristic for review, not proof.

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?

It is a dense, information-rich block where nearly every clause carries distinct behavioral meaning (flag rules, exceptions, limitations). The one weak spot is front-loading a scope caveat instead of the tool's primary action, but overall it is efficient rather than padded.

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?

With no output schema, the description carries the full burden and does so well: it names the returned fields (found, first_published, package_age_days, new_package), explains the 30-day new-package threshold, the 180/365-day flag windows, and clearly scopes what is and is not detectable. An agent has everything needed to call and interpret it.

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% with only two parameters, and the ecosystem description in the schema already states 'npm (full analysis) or pypi (existence and age only)', which the description merely echoes. The description adds no syntax, format, or validation detail beyond the structured fields, so baseline 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 tool's core function (publisher-change analysis for supply-chain risk) is clear, and it enumerates the specific signals it computes (publisher takeover, inactivity window, package age). However, the description opens with a scope limitation ('npm only') rather than a clean verb+resource statement, and it never names or distinguishes itself from plausible siblings like supply_chain_check or typosquat_check.

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?

Usage context is implied through the ecosystem split ('npm (full analysis) or pypi (existence and age only)') and the described detection scenario, but there is no explicit 'use this when...' guidance and no alternatives named. An agent can infer applicability but is not routed against other security tools.

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