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

Annotations already declare readOnlyHint, openWorldHint, and idempotentHint, so the safety profile is covered. The description adds genuinely new behavioral detail: results come newest first in PEP 440 order, and each entry includes publish dates and bump type. It does not mention rate limits or authentication, but for a free read tool that is a minor gap.

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-formed sentence with no waste; the resource and ordering are front-loaded. The leading 'Free:' qualifier is the only slightly unusual element, but it is still informative.

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 usefully discloses the shape of the result (versions with publish dates and bump type) and the sort order. Combined with fully documented parameters, an agent has enough to call it correctly; only auth/rate-limit context is absent.

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%, so the schema already documents 'package', 'from', and 'limit' with examples and defaults. The description adds no syntax or format guidance for pagination ('from', 'limit') beyond what the schema states, so the 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?

States a specific verb and resource: lists published versions of a named PyPI project. It also names the ordering and fields returned, which clearly separates it from pypi_changelog or pypi_breaking_changes. It does not explicitly name a sibling, so a 4 rather than a 5.

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 is only implied by the word 'versions'. There is no statement of when to prefer this over pypi_changelog, pypi_breaking_changes, or dependency_upgrade_plan, and no exclusions or prerequisites. An agent must infer the routing.

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