Card Offers

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

Annotations already cover safety (readOnly, idempotent, openWorld, non-destructive), so the bar is lower; the description still adds real context by disclosing that results are confidence-gated, non-targeted, and carry a verified timestamp plus source URL. This tells the agent about data trustworthiness, which the annotations do not. It does not discuss pagination or staleness limits.

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?

A single sentence that is front-loaded with the core action and packs scope, filtering behavior, and payload shape without a wasted clause. Nothing here is filler.

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 read-only listing tool with an output schema, the description is nearly sufficient: return values need not be spelled out but are summarized anyway, and scope qualifiers are given. The remaining hole is the undocumented 'limit' parameter, which the description and schema both leave silent.

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 only 50%: the 'card' parameter is documented in the schema, but 'limit' has no description anywhere. The description mentions no parameters at all, so it fails to compensate for the coverage gap, particularly the missing semantics of the result cap and its interaction with the 200 maximum.

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?

Specific verb+resource: returning current credit-card welcome-bonus offers, with scoping qualifiers (non-targeted, confidence-gated) and the per-card payload. An agent can distinguish this from siblings like get_transfer_bonuses or get_reward_valuations by resource. It stops short of naming any sibling, so sibling differentiation is inferred rather than stated.

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?

Usage is implied: fetch it when you need live welcome-bonus offers. The 'non-targeted' qualifier hints at a scope boundary (targeted offers presumably live elsewhere), but there is no explicit when-to-use or when-not-to-use guidance and no alternative tool is named.

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