affiliate_impact-advertiser_get_programme_performance

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

With no annotations, the description carries the full burden. It uses 'Fetch' and 'Returns', clearly indicating a read-only operation, and discloses the return type (ProgrammePerformanceRow records). However, it does not explicitly mention side-effect-free behavior, permissions, or pagination, though the read-only intent is unambiguous from the verb.

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 sentences with each earning its place: purpose, usage examples, and return type/companion tools. It is front-loaded and contains no redundant information.

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 data retrieval tool with 8 parameters, no output schema, and no annotations, the description covers the essential aspects: purpose, when to use, return type, and related tools. It lacks explicit parameter-level explanations and pagination details, but the overall context is sufficient for basic usage.

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 0%, so the description must compensate. It adds context for date parameters ('by date') and publisherId ('pair with list_media_partners to discover publisher ids'), but it does not explain pagination parameters (limit, cursor, offset) or date formats. Thus it only partially compensates for the missing schema descriptions.

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 states the specific action ('Fetch per-publisher performance'), the resource ('brand's programme at Impact (advertiser)'), and the metrics (clicks, conversions, gross sale, commission). It distinguishes this tool from siblings by emphasizing 'per-publisher' and the Impact (advertiser) scope, and by contrasting with list_transactions for transaction-level drill-down.

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 explicitly provides trigger phrases ('how is each publisher performing', 'top-earning partners last month') and suggests companion tools (list_media_partners for publisher ids, list_transactions for transaction-level detail), effectively communicating when to use this tool and offering alternatives.

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