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

Beyond the readOnly/idempotent annotations, it discloses auth requirements (agent-scoped bearer key; member/facility keys cannot impersonate), an important semantic caveat that a receipt is not proof of handling, and hard guidance never to substitute another key or mail API after denial. This is rich behavioral context annotations cannot carry.

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?

Front-loads the critical deprecation notice, but the body is dense and partly redundant — 'needs agent.inbox.read' is restated as 'Required scopes: agent.inbox.read', and sentences about rollout switches and SQL authorization are obscure padding.

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 an output schema covering return values and annotations covering the safety profile, the remaining burden is deprecation routing, auth, and result interpretation — all addressed. Nothing an agent needs to call this correctly is missing.

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 100%, so baseline is 3. The description restates the item_id filter role but adds no syntax or semantics beyond the schema, and never mentions the limit parameter.

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 and resource ('Read current authorized inbox retrieval receipts and agent-reported outcomes') and immediately names the successor tool get_inbound_activity. An agent can distinguish this deprecated alias from the live sibling without opening either schema.

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?

Explicitly says 'Deprecated: use get_inbound_activity' — naming the alternative and the condition (alias window) that governs whether this tool should be called at all. It also states the preconditions (agent.inbox.read, agent-scoped bearer key) that gate successful use.

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