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

Annotations already declare this is a non-readonly, non-destructive, non-idempotent creation, so the safety profile is covered. The description adds the useful behavioral note that the vision engine is applied by default to match the Airparser app, but says nothing about duplicate-name handling, failure modes, or what is returned.

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 short sentences, front-loaded with the action, no filler. The trailing clause "as the Airparser app does" is mildly redundant but does justify the default choice.

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 leaves the agent guessing what a successful creation returns (e.g., an inbox identifier) and how to proceed afterward. For a simple two-parameter create tool this is adequate but not complete.

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 coverage is 100% and the enum values for llm_engine are fully documented with trade-offs in the schema itself. The description's only added meaning is restating the vision default, so schema does the heavy lifting and baseline 3 applies.

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?

"Create a new Airparser inbox" gives a clear verb+resource and is unambiguous against siblings, none of which create inboxes. It stops short of naming how it relates to get_inbox/list_inboxes beyond the obvious create-vs-read split.

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 implies when the tool is used (setting up a new inbox) and pins down a default engine choice, but gives no explicit when-to-use/when-not guidance or reference to alternatives. Usage is inferred from the verb rather than stated.

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