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

With no annotations, the description carries full behavioral disclosure. It explains the return behavior across edge cases, notes that failure cases are intentionally indistinguishable, and states the owner-only constraint. It does not describe the exact non-null response shape or auth failure behavior, but it covers the key semantics.

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 compact and front-loaded with the core purpose. Every clause adds useful information, including null semantics, indistinguishability, and ownership requirements. There is no filler or redundant restatement.

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 simple status lookup, the description covers purpose, return-null behavior, ownership, and cross-parameter relationships. The lack of an output schema and a few undocumented parameter descriptions keep it from being fully complete, but an agent gets enough to invoke it correctly in most cases.

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 only 50%, and the description adds some relational context by tying item_id to slug/queue_name and explaining the null case. However, it does not define slug or name parameters, and it mostly relies on the schema for item_id and owner_key meaning. The description partially compensates but leaves gaps.

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 verb and resource: 'Read receipt for one message.' It clarifies what the receipt means ('popped/leased' vs 'ack'd') and what null indicates, which makes the tool's unique role unmistakable among queue siblings. The information-exposure rule further distinguishes it from other queue operations.

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 makes the intended use clear: check whether a message was delivered or processed, and interpret null as no receipt. It does not explicitly name alternatives or state when not to use it, but the context is strong enough for an agent to decide when this tool applies.

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