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

Goes well beyond the annotations: discloses the uniqueness constraint (name unique in project, case-insensitive), the authorization requirement (project lead or admin only), where in the sequence the version lands, and that the response matches list_versions. These are non-obvious constraints an agent could not infer from readOnlyHint/destructiveHint.

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?

Front-loaded with the action and the key constraint; every sentence conveys something actionable. The parenthetical enumeration of fixVersions call sites and JQL examples is somewhat verbose relative to the core task, but it is informative rather than filler.

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 5-parameter create tool with no output schema and no annotation coverage of auth or uniqueness, the description supplies permissions, uniqueness, placement semantics, and the shape of the returned object. An agent has enough to invoke it correctly and interpret the result.

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%, so the parameters are already documented; the description still adds value by stating the name uniqueness/case rule and by clarifying that issue-level versions come from the issue's own project. It adds constraint semantics rather than restating field types.

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 ('Add a version to a project') plus a positional qualifier ('at the end of its sequence'), and defines what a version is with concrete examples. It is clearly distinguishable from update_version and release_version, the latter explicitly claimed elsewhere.

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?

It scopes usage by noting that a version belongs to its project and that any number of them can be attached, and it explicitly routes release behavior to release_version rather than doing it here. It does not explicitly contrast create_version with update_version, so the when-to-use picture is clear but not exhaustive.

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