list_all_accounts

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

With no annotations provided, the description carries the full burden and it does solid work: it discloses what the tool returns (accounts plus capabilities) and the implied read-only nature of a listing operation. It could add notes on account source or result structure, but the output schema covers much of the remaining detail.

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?

Two concise sentences with no filler. The primary action and resource are front-loaded, and the usage guidance is delivered in a short second sentence.

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 parameterless listing tool with an output schema, the description is complete: it names the resource, the returned capability dimensions, and the decision-support purpose. Nothing essential is missing.

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 tool has zero parameters and 100% schema description coverage, so there is nothing for the description to clarify. The baseline of 4 applies, and the description adds no parameter-related content, which is appropriate here.

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 ('List'), a clear resource ('all configured email accounts'), and the key differentiator: it reports per-account capabilities for IMAP, SMTP, Graph API, and EWS. This clearly distinguishes it from sibling tools like imap_list_accounts, which is protocol-scoped.

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 tells the agent when to use the tool: to know which send/read tools to use per account. It does not explicitly enumerate alternatives or exclusions, but the purpose is specific enough that an agent can select it correctly without confusion.

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