create_conversion_pixel

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

No annotations are provided, so the description carries the full behavioral burden. It does disclose the return-value consequences (pid used for event attribution and listing sampled events) and implies a persistent side effect via 'create.' But it omits auth requirements, duplicate-name behavior, and whether the pixel is immediately active/listable — meaningful gaps for a write operation with zero annotation coverage.

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?

Two sentences and roughly 35 words, with the core create action front-loaded in the first sentence and return semantics plus workflow sequencing compactly delivered in the second. Every clause earns its place; there is no filler or redundancy.

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?

With no output schema present, the return-value disclosure (pid and its uses) is necessary and provided, and the chaining hint covers the immediate next actions an agent needs. Remaining gaps—auth prerequisites and idempotency/duplicate behavior—are minor for a simple 3-parameter, 1-required-field create tool, so the definition is near-complete for its complexity.

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 67%: name and client_type have descriptions ('Pixel name 3–1000 chars', 'Client type (currently only web)'), while ad_account_id has none. The description partially compensates by anchoring the operation 'for the ad account,' but it does not clarify ad_account_id's expected format or add meaning beyond the schema for the other parameters.

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?

States a specific verb and resource ('Create a conversion pixel (client data source) for the ad account'), names the concrete return artifact (pid), and explains its purpose (event attribution, listing sampled events). It also orients the operation within the conversion-pixel workflow by naming the two sibling chain steps, distinguishing it from create_conversion_api_key and create_conversion_event_setting.

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 'Chain to create_conversion_api_key and create_conversion_event_setting' instruction gives explicit sequencing, signaling that this tool is the first step of a setup workflow. However, it offers no when-not-to-use conditions or alternatives (e.g., checking list_conversion_pixels for an existing pixel before creating a duplicate), so it stops short of a full 5.

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