outlook_attach_to_draft

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

Annotations only declare readOnly=false and destructive=false, and the description goes well beyond that: it discloses the >3MB upload-session auto-switch, the path-resolution/security rule (bare filename looked up in attachments_dir, outside paths refused), and the return of new attachment IDs. That is substantive operational context.

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?

Front-loads the core action and size-threshold behavior before the pathing detail; every sentence carries information. The parenthetical about the default directory is dense but earns its place.

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?

With no output schema, the description usefully states what is returned (new attachment IDs) and how they feed into removal. Combined with the path and size behavior, an agent has enough to invoke it correctly, though draft_id semantics are not spelled out.

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?

With 0% schema coverage, the description compensates strongly for attachment_paths by explaining resolution rules, the bare-filename case, and the outside-path rejection. draft_id is only implied by 'existing draft', but it is a self-evident identifier, leaving only a minor gap.

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?

States a specific verb and resource — 'Add attachments to an existing draft' — which clearly separates it from siblings like outlook_send_with_attachments and outlook_create_draft. An agent can identify its scope without opening 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?

Usage is implied by 'existing draft' and it cross-references outlook_remove_draft_attachment for cleanup, but it never explicitly states when to prefer this over alternatives such as attaching at send time. Guidance is present but inferential.

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