ClockNext: create unit

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

Annotations already mark this as a write operation (readOnlyHint=false), and the description aligns with that. It adds valuable behavioral context beyond the schema: the agentKey is a durable identity unique org-wide, and a rename never changes it. It also discloses tier constraints (1–50, ordered, only last may be null). It doesn't cover failure modes, but given annotation coverage, this is a solid enhancement.

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 a single dense paragraph, but it follows a logical order: definition, pricing options, tier constraints, dashboard fallback, plan relationship. Some details duplicate schema (e.g., tier null rule), but there is no filler. It could be improved with line breaks or bullet points, but it remains focused and readable.

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 create tool with 7 parameters and no output schema, the description covers the domain thoroughly: what a unit is, when to use it, pricing models, tier rules, and how plans consume the unit. The only notable gap is not describing the return value or success/error behavior, which would be more critical in the absence of an output schema. Overall, it's nearly complete.

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 conceptual meaning for all parameters: it explains that agentKey is the durable reported identity, flatPrice defaults to 0 and is for FLAT pricing, pricingType distinguishes FLAT vs tiered models, and tiers have ordering/null-bound rules. This enriches the raw schema definitions with domain context.

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 'Create a unit type' — a specific verb and resource — and immediately defines what a unit is (a metered usage unit with a durable agentKey). It explicitly distinguishes this from sibling create_* tools by scoping to fixed-cost/non-LLM events and explaining how plans reference units. This is a clear, non-tautological purpose statement.

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 explicit usage guidance: 'PREFER the dashboard... use this tool as the fallback.' It also provides domain rules (units are for fixed-cost/non-LLM events, one event = one unit) and a prerequisite relationship ('A plan meters it via a UNIT component'). This goes beyond generic context to actionable when-to-use/fallback guidance.

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