get_jmap_session

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

No annotations are provided, so the description carries full burden. It clearly states the tool returns session information, implying no side effects. While it does not explicitly state 'read-only' or 'safe', the description is transparent enough for a low-risk informational tool.

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 two short sentences with no unnecessary words. The first sentence states the core function and outputs; the second provides usage guidance. Every sentence earns its place, making it highly efficient.

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 simplicity (no parameters, returns session info), the description is complete. It mentions the key output fields (capabilities, account IDs, username, feature availability) and provides a usage reason. The output schema exists to detail structure, so the description doesn't need to repeat that.

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 zero parameters with 100% description coverage (trivially). The description adds value by explaining what the output contains, which helps the agent understand the tool's purpose even without parameters. The baseline for 0 parameters is 4, and no additional parameter detail is needed.

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 clearly states the verb 'Return' and the resource 'JMAP session', listing key outputs (capabilities, account IDs, username, feature availability). It distinguishes itself from all sibling tools, which focus on email/mailbox operations, by being the only session discovery tool.

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 explicitly advises using this tool to discover features and scopes available with the API token, giving a clear usage scenario. It does not provide when-not-to-use or compare to alternatives, but the context is sufficient for an agent to treat it as an initial informational step.

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