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

The annotations already cover read-only, idempotent, non-destructive behavior, so the safety profile is established. The description adds useful context beyond annotations by stating 'No auth required', citing the data source, and enumerating returned fields. No contradictions with annotations.

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 three concise sentences, front-loading the main purpose first and then giving returns, roles, requirements, auth, and source. Every sentence carries useful information with no fluff or repetition.

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 read-only lookup with an output schema, the description covers purpose, required input, optional filter, roles, auth, and source. It does not mention how to discover the demarcation code (e.g., via samuni.reference.municipalities), which is a minor gap given the siblings list.

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 the schema documents both parameters fully. The description reinforces the meaning of demarcation_code and role with examples, but it does not add substantial new semantics beyond what the schema already provides.

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 clearly states a specific action ('Get contact details') and resource ('senior officials of a South African municipality'). It is specific enough to distinguish from the broader reference tool samuni.reference.municipalities, though it does not name any sibling tools explicitly.

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 gives clear context on when to use the tool: it requires a demarcation code, optionally filters by role, needs no auth, and lists common role names. It does not explicitly state when not to use it or point to alternatives like samuni.reference.municipalities for code lookup.

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