btcpay-mcp

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It successfully explains the auto_approve mechanism ('without manual review'), return values ('pull payment ID, payment link, and configuration'), and date formatting. However, it omits other critical behavioral traits like idempotency, error conditions, or side effects.

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 uses a clear docstring format (Args/Returns) that organizes information efficiently. Despite documenting 6 parameters, there is no extraneous text—every line serves to document inputs or outputs. The structure is slightly formal but highly readable.

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 creation tool with 6 parameters, zero schema coverage, and no annotations, the description provides comprehensive input documentation and summarizes the output. It appropriately leverages the existence of an output schema (per context signals) by only summarizing return values rather than detailing them, while focusing descriptive effort on the poorly-documented inputs.

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?

Given 0% schema description coverage, the description fully compensates by comprehensively documenting all 6 parameters. It provides data types, examples (e.g., '0.01' for amount, 'BTC'/'USD' for currency, ISO 8601 format for expires_at), default values, and semantic meaning for each parameter, including the business logic of auto_approve.

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 ('Create') and resource ('pull payment') and specifies concrete use cases (donations, subscriptions, payroll) that help distinguish it from sibling tools like create_invoice or create_payment_request. However, it does not explicitly contrast with these siblings to clarify when to choose one over the other.

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 implies usage through specific examples (donations, subscriptions, payroll), giving the agent context on when this tool is appropriate. However, it lacks explicit 'when-not-to-use' guidance or references to alternative tools for different payment flows.

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