IMAP Mini MCP

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

With no annotations provided, the description carries the full burden. It discloses that this is a mutation tool ('Replace'), specifies the folder restriction, and describes the return format. However, it lacks details on permissions, error handling, or side effects like whether previous content is overwritten or archived.

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 front-loaded with the core purpose in the first sentence, followed by a critical constraint and return details in two concise sentences. Every sentence adds value without redundancy, making it efficient and well-structured.

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 mutation nature, 7 parameters, and no annotations or output schema, the description is mostly complete: it covers purpose, constraints, and return values. However, it could improve by addressing authentication needs or error cases, leaving minor gaps for a tool with significant parameters.

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 description coverage is 100%, so the schema fully documents all 7 parameters. The description adds no additional parameter semantics beyond what the schema provides, such as format examples or constraints, meeting the baseline score for high schema coverage.

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 specific action ('Replace an existing draft with new content'), identifies the resource ('draft'), and distinguishes it from siblings by specifying it only works on emails in the Drafts folder, unlike tools like 'move_email' or 'draft_reply' that might handle other folders or operations.

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 provides clear context for when to use this tool ('id must refer to an email in the Drafts folder') and implicitly excludes other folders, but does not explicitly name alternatives like 'create_draft' for new drafts or specify when not to use it beyond the folder constraint.

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