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

Annotations already provide readOnlyHint, idempotentHint, and destructiveHint, so the safety profile is well established. The description adds meaningful context beyond these annotations: it is a pure static lookup with no external calls or data retrieval, and it returns a safe next action. This is useful behavioral disclosure, though the description does not detail response formatting.

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 two sentences with no filler. The first sentence states the core purpose and output, and the second provides a critical exclusion list that disambiguates the tool from its siblings. Everything included earns its place.

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 static lookup tool with two well-documented parameters and strong annotations, the description is complete enough for an agent to invoke it correctly. The absence of an output schema is mitigated by the explicit promise of an explanation and a safe next action, and there are no hidden side effects, auth requirements, or rate limits to disclose.

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%, and both parameters are already well documented in the input schema: status has a full enum plus a definition, and context has detailed usage rules including word count and third-person perspective. The tool description adds no additional parameter semantics, so baseline 3 is appropriate.

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 names a specific action ('Explain') and a specific resource ('one Bucky coverage or per-fact provenance status'), adds the deliverable ('safe next action'), and differentiates it from the sibling analysis tools by explicitly labeling it a 'pure static lookup.' This leaves little ambiguity about what the tool does.

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 clearly communicates when this tool is not appropriate by enumerating exclusions: it does not inspect an address, retrieve property data, or call a database, geocoder, AI model, or third-party API. It does not explicitly name sibling alternatives like runFeasibilityAnalysis or getFeasibilitySnapshot, but the static-lookup framing provides strong selection guidance.

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