xendit-mcp

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

With no annotations, the description carries full burden but provides minimal behavioral insight. It mentions supported countries and transfer types, but lacks critical details: whether this is a live transaction or simulation, typical processing times, error handling, authentication requirements, rate limits, or idempotency (externalId hints at idempotency but not stated). 'Send money' implies a write/mutation, but safety profile is unclear.

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?

Single sentence is appropriately concise and front-loaded with core purpose. No redundant phrases, though it could be slightly more structured (e.g., separating scope from action). Every word earns its place, but lacks elaboration on critical behavioral aspects.

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 financial write operation with 7 parameters, no annotations, and no output schema, the description is insufficient. It doesn't explain what happens after invocation (e.g., returns a transaction ID, status), error conditions, security requirements, or idempotency guarantees. The agent lacks context to use this tool safely and effectively.

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 100%, so parameters are well-documented in the schema. The description adds marginal value by hinting at geographic scope (Indonesian/Philippine banks) which relates to bankCode and currency, but doesn't explain parameter interactions (e.g., currency-bank compatibility) or provide examples beyond bankCode enumeration. Baseline 3 is appropriate as schema does heavy lifting.

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 action ('Send money') and target ('to a bank account or e-wallet'), with geographic scope ('Indonesian and Philippine banks'). It distinguishes from siblings like create_invoice (payment collection) and get_disbursement (retrieval), but doesn't explicitly contrast with list_disbursement_banks (bank listing).

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. It doesn't mention prerequisites (e.g., sufficient balance), or contrast with other disbursement-related tools like list_disbursement_banks (for bank codes) or get_disbursement (for status checks). Usage is implied by the action but not contextualized.

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