Inbox summary

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

With readOnlyHint=true and openWorldHint=true already in annotations, the description adds useful behavioral context: the tool is composite, surfaces only the last message per conversation, and must not auto-reply. No annotation contradiction is present.

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-load the behavior, then the workflow, then the guardrail. Every clause earns its place; there is no redundant phrasing or filler.

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 composite fetch/group tool with no output schema, the description explains what is delivered, when to use it, and the safe following actions. The only real gap is the complete absence of parameter guidance.

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?

Input schema coverage is 0%, and the description does not explain max_results or max_conversations. The parameter names and numeric bounds in the schema are self-explanatory, but the description adds no meaning about what each parameter controls or how they interact.

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?

The description states a specific composite operation: 'fetch recent DM events and group by conversation with the last message.' This clearly identifies the tool as an inbox summary and distinguishes it from raw DM-event listing or sending tools.

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 explicitly routes the agent: 'Use this to triage inbox, then x_organic_list_dm_conversation + x_organic_send_dm (confirm) to answer. Do not auto-reply.' It provides a concrete workflow and a hard constraint, making the tool's role clear relative to siblings.

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