subscriptions__usage_summary

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

With no annotations provided, the description carries the full burden. It says 'Return' which suggests read-only, but does not explicitly confirm idempotency, safety, or any behavioral traits like permissions or data freshness. For a usage summary tool, more transparency is needed.

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 sentence that fits the purpose. The bracketed prefix front-loads context. While it is somewhat dense, it avoids unnecessary words and is efficiently structured.

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?

Given the lack of output schema, the tool's complexity (included/overage usage, periods, lineage, totals), and detailed sibling names, the description is insufficient. It does not explain return value structure, pagination, date range, or how to interpret results, leaving an agent underinformed.

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 single parameter account_id is not explained in the description. The phrase 'bearer-owned' hints that the account is tied to the bearer, but it does not clarify what identifier is expected (e.g., subscription ID, customer ID). With 0% schema coverage, the description should compensate but fails to provide sufficient meaning.

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 it returns usage summary data (included and overage usage) with lineage and conservation totals, clearly identifying the tool's purpose. The context prefix [subscriptions — B2B monthly seats, entitlement quota, overage, and MRR] helps distinguish it from sibling tools like mrr_summary. However, jargon like 'bearer-owned' and 'exact catalog lineage' may obscure meaning.

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 explicit guidance on when to use this tool versus alternatives such as subscriptions__mrr_summary or subscriptions__get_plan. The description implies it is for usage summaries but does not provide context or exclusions.

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