Get List Fields

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

Annotations declare readOnlyHint=true and idempotentHint=true, which the description supports by describing a read-only operation. The description adds value beyond annotations by detailing the return structure, field classification, value types, and pagination behavior (cursor, limit). However, it omits the responseFormat parameter, which is a minor gap.

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 well-structured: a concise first-line summary, bullet points for parameters, a clear JSON example for the return value, and separate sections for field and value types. Every sentence adds value without redundancy or fluff.

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?

Given the absence of an output schema, the description provides a complete output example with all relevant fields and types. Combined with thorough annotations (readOnly, idempotent) and full parameter coverage, it leaves no major gaps for a standard read-only list fields retrieval tool.

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?

With 100% schema description coverage, baseline is 3. The description adds context for listId (source from affinity_list_lists) and explains pagination parameters (cursor, limit). This extra clarification improves the agent's understanding beyond the schema alone. The responseFormat parameter is not described, but its presence in the schema is sufficient given high coverage.

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 'Get field definitions for an Affinity list' with a specific verb and resource. It details the types of fields returned (list-specific, global, enriched), effectively distinguishing it from siblings like affinity_get_field_values which retrieves field values rather than definitions.

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 usage when you need the schema of fields for a list but does not explicitly state when to use this tool versus alternatives or provide exclusions. It lacks guidance on when not to use it, leaving the agent to infer based on purpose alone.

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