audiences

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

With no annotations, the description fully covers behavioral traits: declares MODE (mixed read+write), AUTH (OAuth 2.0), CREDITS (free list/get; create costs 0.5 credits and needs confirmation_token), OUTPUT (returns segments with specific fields), and SIDE EFFECTS (modifies data, can activate/deactivate). 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 well-structured with clear sections (MODE, AUTH, CREDITS, OUTPUT, SIDE EFFECTS, WHEN TO USE) and each sentence provides relevant information. It is comprehensive but not overly verbose, earning high marks with a slight deduction for its length.

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 tool's complexity (multiple actions, two parameters, no output schema), the description is remarkably complete. It covers usage context, authentication, credits, side effects, and output format. The only minor omission is a concrete example of confirmation_token handling, but overall it meets the needs for correct invocation.

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 covers 100% of parameters. The description adds significant value: for the action parameter, it details each enum value's behavior (read/write, cost, required sub-params). For network_code, it explains its purpose and how to obtain it. This goes well beyond the schema's minimal description.

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 'Manage GAM first-party audience segments' which is a specific verb+resource. It distinguishes from sibling tools by explicitly noting that for targeting segments on line items, one should use the targeting tool instead.

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 a dedicated 'WHEN TO USE' section explaining when to use this tool (managing first-party data segments) and when not (use targeting tool). Also mentions AUTH requirements (initiate_gam_auth first) and CREDIT costs, giving clear context for usage.

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