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

The phrase 'Key discarded' is a useful hint that the input is not stored or returned, but with no annotations the description must disclose the behavior more fully. It does not state whether the tool returns a boolean, throws on mismatch, or what happens when multiple schema parameters are supplied.

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 two short sentences are front-loaded and contain no filler; the first states the purpose and the second adds a behavioral note. It earns brevity credit, though the lack of content prevents a perfect score.

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 simple shape-checking tool with no output schema and no annotations, the description should at least specify the expected key format, the target parameter, and the return/error behavior. It provides none of these, and the nine unrelated parameters compound the ambiguity.

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%, but the description fails to identify which of the nine parameters represents the Jira issue key. The schema describes ref, url, city, feed, host, json, path, zone, and query, none clearly related to Jira. This is misleading rather than merely incomplete.

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 essentially restates the tool name: 'Check a Jira issue key shape' adds no detail about what a valid Jira key looks like or which model input it applies to. The schema exposes nine unrelated string parameters, none labeled as a Jira key, so the stated purpose does not connect to the actual call contract.

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?

There is no guidance about when to prefer this tool over sibling shape-checkers such as github-repo-shape or domain-shape, and no mention of what kinds of strings are appropriate. The only implied use is 'for a Jira key,' which is not enough given the broad, unrelated schema.

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