Create the missing goals of a counter

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

Beyond the annotations, the description discloses the idempotency check by event identifier, the read-back validation with explicit error semantics, the preview behavior, and the confirmation phrase safety mechanism. These are meaningful behavioral details that annotations alone do not provide.

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 front-loaded with the core operation and every subsequent sentence adds distinct value: idempotency behavior, read-back validation, timing warning, preview behavior, and confirmation safety. No sentence is wasted.

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 tool with no output schema, the description clearly explains both preview output and error semantics after read-back. Combined with full schema coverage and annotations, an agent has enough to select and invoke the tool correctly.

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 coverage is 100%, so the baseline is 3. The description adds useful semantics for confirmation (preview without it, and it names the counter) and for counter (numeric id), which improves parameter understanding beyond the schema.

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 opens with a specific verb and resource: "Create JavaScript-event goals in one Metrika counter." It further distinguishes itself from siblings by emphasizing idempotent creation of only missing goals, which is unique among the direct_* family.

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 gives clear operational context: goals must exist before the first ad click, and calling without confirmation yields a preview. It does not explicitly name alternatives or when-not-to-use, but it supplies enough context for an agent to recognize when this tool applies.

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