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

With no annotations provided, the description carries the full burden of behavioral disclosure. It explains that permission is required, returns the new issue key, and details a subtle behavior: unresolved mentions are not refused but stored as written, with 'unresolvedMentions' being the only signal. This goes well beyond a simple 'creates an issue' and provides crucial insight into how the tool handles edge cases.

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 approximately 70 words, consisting of four concise sentences. It front-loads the core purpose and return value, then covers permission and the mention behavior. There is no redundant or filler language; every sentence contributes to the agent's understanding.

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?

Given the tool's complexity (9 parameters, no output schema), the description is fairly complete. It mentions the return values (issue key, notified, unresolvedMentions), permission requirements, and the mention behavior. While it doesn't cover error cases or rate limits, the combination of schema descriptions and this behavioral context is sufficient for correct invocation. The missing details are minor compared to what is provided.

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 input schema has 100% description coverage, so the baseline is 3. The description adds value by explaining the behavior around mentions and handles, which directly impacts parameters like assignee and description. It clarifies that a wrong handle is stored as written and never refused, a nuance not present in the schema. This enhances understanding of parameter usage beyond the schema's basic descriptions.

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 states a specific verb ('Create'), a resource ('issue'), and a scope ('in a project visible to this token'). It distinguishes from siblings like update_issue and create_project, making it clear this tool is for creating new issues. The mention of returning the new issue key further clarifies its purpose.

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?

The description clearly indicates the tool's purpose, which implicitly suggests when to use it (to create a new issue). However, it does not explicitly state when not to use it or name alternatives like update_issue or set_issue_fields for modifying existing issues. There is no explicit guidance on selecting between siblings, so it relies on the reader to infer usage.

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