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

With no annotations present, the description carries the full burden. 'Key discarded' does disclose that the key is not retained, but it omits the return value, error behavior, and what happens for malformed input. The seven unrelated schema fields are not explained at all.

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 description is very short and front-loaded with the core action; the discard note adds an extra constraint without filling space. It is lean, though too terse to fully support invocation.

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 tool with seven heterogeneous parameters and no output schema, a one-sentence description is critically incomplete. An agent cannot tell which field to pass as the Jira key or what a successful shape check returns.

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?

The schema already describes each property, but the description adds no mapping between them and the 'Jira issue key.' It refers to a 'key' that does not appear as any of the seven property names, leaving an agent unable to determine whether ref, url, or another field carries the key.

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 opens with a specific verb ('Check') and resource ('Jira issue key shape'), which states the tool's purpose and distinguishes it from sibling shape checkers like github-repo-shape or domain-shape. It falls short of a 5 because it never links the check to any actual input field in 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?

There is no guidance about when to use this tool instead of a sibling, nor any conditions that indicate suitability. 'Key discarded' is a behavioral constraint rather than routing information, so the agent is left without usage context.

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