Receive messages (blocks until one arrives or timeout)

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

With no annotations provided, the description carries the full behavioral burden. It discloses that messages are consumed, that it blocks conditionally, that it is event-driven, and that an empty array can be returned on timeout. This is strong coverage for a simple receive tool.

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 sentences deliver all essential information: action, blocking behavior, and return value. Every phrase earns its place, and the title reinforces the key blocking semantics without duplication.

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 purpose, consumption, blocking behavior, timeout, and return format, which is sufficient for a simple tool with no output schema. Minor gaps remain, such as explicitly stating what happens with block=false, but this is inferable from the conditional phrasing.

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%, so the schema already documents all parameters. The description adds valuable relational context by explaining how 'block' and 'timeout_ms' interact when no messages are pending, which goes beyond the individual parameter descriptions.

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 uses specific language ('Fetch and CONSUME pending messages for your session') that identifies the exact verb, resource, and scope. It clearly distinguishes this from sibling tools like bus_peek by emphasizing the consuming/destructive nature.

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?

It provides clear context for when to call the tool: retrieve pending messages, optionally blocking until one arrives. It does not explicitly name alternatives or exclusion cases, but the 'CONSUME' wording implicitly tells the agent not to use this for inspection-only scenarios.

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