create_segment

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

Discloses no destructive side effects, respects read-only/dry-run, explains static vs dynamic behavior. Lacks detail on idempotency or failure modes but sufficient given no 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?

Well-structured with overview, behavioral notes, args list, and returns. Front-loaded with purpose, every sentence adds value.

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?

Covers all necessary aspects for a creation tool: parameters, behavior, output fields, and relationships to siblings. Output schema reduces need for return details, but returns are included anyway.

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?

Input schema has 0% description coverage; the description compensates fully by detailing each parameter, including list_id format, static defaults, and conditions requirements.

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?

Clearly states the tool creates a segment or tag, distinguishes static vs dynamic, and differentiates from siblings like tag_member and add_members_to_segment.

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?

Provides explicit when-to-use: static vs dynamic, and alternative tools (tag_member, add_members_to_segment). Also includes auth and rate limit info.

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