update_transaction

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

No annotations provided, so description carries full burden. It discloses that only supplied fields are changed (partial update) and that card identity and type are immutable. Could add more detail on validation or existence requirements, but overall good transparency.

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?

Three sentences, each serving a distinct purpose: purpose, partial update behavior, constraints/auth. No redundant information, front-loaded with main action.

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?

Covers key aspects: update behavior, immutable fields, auth. No output schema needed. Could mention that the transaction must exist, but implied. For an update tool with nested param, it is sufficiently complete for agent understanding.

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 description coverage is 50% (id parameter has description, patch object does not). The description adds context that patch is a partial update and lists immutable fields. However, it does not describe individual patch fields beyond what schema provides, so baseline 3 is appropriate.

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 it updates an existing transaction by ID. It specifies that only supplied fields change, and explicitly distinguishes from delete-and-recreate for immutable fields (card identity, type). This differentiates it from sibling tools like record_transaction and delete_transaction.

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?

Provides explicit guidance: when to use (update transaction), when not to (for card identity/type changes, use delete and re-create). Also mentions the required IWMM_API_KEY, giving clear context on prerequisites.

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