Create a usage meter between a provider and a consumer agent.
unit: what is being counted (call, token, kwh, ...). Price is in minor
currency units (cents) per unit. Returns the meter_id.| Name | Required | Description | Default |
|---|---|---|---|
| unit | Yes | ||
| consumer | Yes | ||
| currency | No | USD | |
| provider | Yes | ||
| sla_target | No | ||
| price_minor_per_unit | Yes |
| Name | Required | Description | Default |
|---|---|---|---|
| result | Yes |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description must disclose behavioral traits but only mentions it returns the meter_id. It omits side effects, authorization requirements, idempotency, or data persistence, which is insufficient for a creation tool.
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 concise with two sentences and a clarification line, no redundant words. It efficiently communicates the core action and key parameter semantics.
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?
Despite having an output schema, the description only lists the return value as meter_id. It does not explain all 6 parameters, defaults (currency, sla_target), error conditions, or usage context, leaving significant gaps for a complex tool.
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?
The description adds meaning for 'unit' and 'price_minor_per_unit' (e.g., unit is what is counted, price in cents per unit), but does not explain provider, consumer, currency, or sla_target. Given 0% schema coverage, it partially compensates but misses key 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?
The description clearly states the tool creates a usage meter between provider and consumer, using a specific verb ('Create') and resource ('usage meter'). It distinguishes from sibling tools like list_meters or flag_meter, as creation is unique.
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?
No guidance is provided on when to use this tool versus alternatives like record_usage or flag_meter. It does not mention prerequisites or scenarios, leaving the agent to infer usage context.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.
Each tool targets a distinct aspect of usage metering: creating meters, recording events, generating reports, flagging synthetic data, closing periods, and verifying chain integrity. No two tools have overlapping purposes.
All tool names follow a consistent verb_noun pattern in snake_case (e.g., close_period, create_meter, list_events). No deviations or mixed conventions.
With 11 tools, the set is well-scoped for a metering server. It covers creation, recording, listing, reporting, admin flags, period closing, and chain verification without being unnecessarily large.
The core lifecycle is covered: create meter, record usage, list events, generate reports, close period. Missing are tools to update/delete meters or retrieve invoices, but these are minor gaps given the immutable design intent.