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

With no annotations, the description carries the burden of behavioral disclosure. It transparently explains the tool's verification action and the inherent limitation that conclusions depend on not having the producing install's keys, which is valuable context. However, it does not explicitly state whether the operation is read-only, whether it can fail or throw errors, or what happens if the receipt is invalid – though these may be partially covered by the output schema.

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 a single sentence that front-loads the core action ('Verify a run receipt and narrate the result') and then enumerates the key things the narration covers. It is dense but not bloated; every phrase adds relevant detail. The list format within the sentence makes it scannable, though it is slightly longer than necessary.

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 tool has one parameterley documented, an output schema, and a clear description of what the tool produces. The main gap is that, in the presence of sibling verify_receipt and verify_chain, the description does not clarify the decision between explanation and raw verification. For an agent, this missing routing guidance makes the definition adequate but not fully complete.

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 input schema already covers the single parameter with a detailed description, saying it can be a string for byte-exact verification or a parsed object. Since schema description coverage is 100%, the baseline of 3 applies. The tool description itself adds no extra parameter semantics, but the parameter is simple and well documented in the 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?

The description states a specific verb ('Verify') and resource ('a run receipt') and adds a distinctive outcome: narrating the result in plain language, including what the run recorded, which chains recomputed, and where the first divergence is. This clearly differentiates it from sibling verify_receipt, which likely only verifies without the narrative layer. It doesn't explicitly name any sibling, but the behavioral detail supplies enough distinction.

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 implies when to use this tool: when you need a plain-language explanation of a run receipt, including auditor-relevant conclusions. However, it never explicitly states 'use verify_receipt for a structured/machine-readable result' or any exclusion criteria. The guidance is present but not explicit enough to fully prevent ambiguous tool selection.

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