get_billing_campaign

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

With no annotations provided, the description bears the full burden of behavioral disclosure. It explains the return value (active campaign or null) and implies no side effects, but doesn't discuss authentication requirements or potential rate limits. While adequate, it could be more explicit about being read-only (though inferred).

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 two sentences long, front-loads the purpose, and every sentence adds value. No redundant or extraneous information.

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 tool has no parameters and no output schema, the description adequately covers what it does, its return type, and a primary use case. It doesn't detail the campaign structure or auth, but for a simple read tool this is sufficient.

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 tool has no parameters, and the schema coverage is 100% (no parameters to cover). The description adds no parameter details, which is acceptable as there are none. Baseline of 4 applies for zero-parameter tools.

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 gets the currently-active credit/deposit-match campaign and specifies it returns {campaign: null} when none is running. It distinguishes itself from sibling tools like get_bonus_ledger or get_credit_balance by focusing specifically on the promotional campaign.

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 advises checking before suggesting a top-up to catch a bonus match, providing a clear use case. It doesn't explicitly exclude other scenarios or mention alternatives, but the context is adequately clear for this simple read operation.

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