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

Annotations already declare readOnlyHint and openWorldHint=false; the description reinforces this with 'Pure computation, free', telling the agent there are no side effects or costs. It also discloses the return shape (-1/0/1 plus a readable meaning) despite no output schema existing, though it says nothing about behavior on malformed version strings.

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?

Two sentences, zero waste, with the core operation front-loaded and the return contract immediately after. Nothing is repeated from the schema.

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 two-string, no-output-schema tool this is nearly complete: the operation, pre-release handling, and return values are all stated. The only missing piece is error behavior for invalid or non-semver inputs, which neither schema nor description addresses.

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%, with examples ('1.2.3', 'v2.0.0-beta.1') already in the property descriptions, so the baseline is 3. The description's mention of pre-release tags adds slight context but no format or ordering rules beyond what the schema shows.

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 ('Compare two semantic versions') and adds scope detail ('including pre-release tags'), which is exactly the nuance an agent needs to distinguish this from siblings like bursia_levenshtein or bursia_date_diff. The tool's identity is unambiguous without opening the schema.

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 operation itself; there is no explicit statement of when to prefer this over a generic string diff or what to do with non-semver input. The closing note 'Pure computation, free' hints that it is a cheap, safe call, but no alternatives or exclusions are named.

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