Brex MCP Server

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

With no annotations provided, the description carries full burden for behavioral disclosure. It mentions the tool 'Returns transaction list with money annotation' which provides some output context, but doesn't address important behavioral aspects like pagination, rate limits, authentication requirements, error conditions, or what 'legacy endpoint' implies for reliability/deprecation.

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 appropriately concise with two sentences that each serve a purpose. The first sentence states the core functionality, the second provides important context about it being a legacy endpoint and mentions the return format. No wasted words, though it could be slightly more 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?

For a transaction retrieval tool with no annotations and no output schema, the description is incomplete. It mentions the return includes 'money annotation' but doesn't describe the structure of the transaction list, pagination behavior, error responses, or how this legacy endpoint differs from newer alternatives among the many sibling tools.

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 the schema already documents both parameters thoroughly. The description doesn't add any meaningful parameter semantics beyond what's in the schema - it mentions 'by account ID' which is already covered, but doesn't explain format requirements, constraints, or usage patterns for the parameters.

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's purpose: 'Retrieve transactions for a specific Brex account by account ID' - this is a specific verb+resource combination. However, it doesn't distinguish this tool from its many sibling transaction-related tools (e.g., get_card_transactions, get_cash_transactions), which would require a 5.

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 provides minimal guidance - it mentions this is a 'Legacy endpoint for general transaction retrieval' but doesn't explain when to use this tool versus the many sibling transaction tools available. No explicit when/when-not guidance or alternative recommendations are provided.

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