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

Annotations already cover read-only, idempotent, non-destructive. The description adds that a row proves event recording, not OCR accuracy or physical completion, explains proposals never charge credits or act autonomously, and notes image URLs are never issued to agents. These are behavioral details beyond 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 description is detailed but every sentence adds necessary context for correct usage. It is front-loaded with the core purpose and then covers scope, key types, and policy restrictions. It is appropriately structured for a tool with multiple behavioral caveats, though slightly dense.

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?

The description covers event semantics, filtering, auth scope, key differences, proposal behavior, policy checks, and the image URL restriction. With an output schema present, the description is nearly complete. Minor omissions like pagination details are already in the schema.

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?

The description mentions item_id narrowing to one item, but does not describe limit or offset. Schema provides defaults and constraints for all params. Given 0% schema description coverage, the description only partially compensates; it adds meaning for item_id but leaves limit/offset to schema.

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 the verb 'Read' and resource 'inbound timeline' via the API endpoint, enumerates event types (received, action proposed/requested/started/completed/rejected) and ordering (newest first). Clearly distinguishes from siblings like get_inbound_item or list_inbound_items by focusing on activity events.

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?

Provides explicit context on when to use: read the inbound timeline, with optional item_id filtering. Details scope requirements (inbound.read), distinguishes member vs agent key behavior, and includes a policy directive ('Stop on denial; never switch keys or mail APIs to bypass it'). While it doesn't name alternatives, the context makes the use case clear.

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