Antal mejl i en mapp

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

Annotations already declare readOnly/idempotent/non-destructive, but the description adds real behavioral value: it throws on a nonexistent folder and on container folders (Folders/Labels, selectable:false), pre-empting a whole class of failed calls.

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 sentences plus a short Args block; the core behavior and the error condition are front-loaded, with no filler beyond the compact argument note.

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 single-param read tool with strong annotations and no output schema, the description covers purpose, default, and failure modes adequately; only the exact return shape is left unspecified.

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 0%, so the description must carry the load. It defines mailbox as a folder name, notes the INBOX default, and implicitly constrains valid values via the selectable:false distinction from list_mailboxes.

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 (Hämta) and the exact payload: count of messages and unread in a folder. This is distinguishable from list_emails/get_email_headers, which return content rather than aggregate counts.

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 (check mailbox stats) rather than stated. It references list_mailboxes to explain which folders are valid, but never says when to prefer this tool over e.g. list_emails or check_new_emails.

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