resolve_folder

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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so safety is covered. The description adds genuinely new behavior: the resolution strategy (SPECIAL-USE flags first, fallback to common folder names) and the failure mode (returns null if no matching folder exists). What is missing is any note on provider variance in failure or caching, but the disclosure goes well beyond the annotations.

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 core behavior and example lead, followed by the fallback rule and null-return, then the arg notes — a sensible front-loaded order. The Args block is a small amount of overhead but earns its place given the 0% schema coverage.

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?

An output schema exists so return-shape explanation is unnecessary, and the description still covers the null case and both parameters. For a two-parameter resolver with full annotation coverage this is essentially complete; only explicit routing versus list_folders is absent.

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% and neither parameter carries an enum in the schema, so the description does the heavy lifting: it enumerates the eight valid role values with a case-insensitivity note, and identifies account as 'Account name from list_accounts'. That is a large compensation for the schema gap, though it does not state the exact expected casing/format of the returned account string.

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 precise verb+resource ('resolve a special-use role to the provider-specific folder name') and immediately grounds it with concrete examples ('sent' becomes 'Sent Messages' on iCloud, '[Gmail]/Sent Mail' on Gmail). This is unmistakably distinct from sibling tools like list_folders, which enumerate folders rather than map a role to a provider name.

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 rather than stated: naming 'list_accounts' as the source of the account argument tells the agent the prerequisite chain, and the role vocabulary implies this precedes move_email/delete_email calls. However there is no explicit when-to-use statement and no exclusion versus list_folders, so the agent must infer the routing.

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