PayFast MCP Server

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. While it mentions the tool retrieves 'transaction history' and supports date range and pagination, it doesn't describe what the return format looks like, whether results are sorted, if there are rate limits, what authentication is required, or whether this is a read-only operation. For a tool with 4 parameters and no annotation coverage, this leaves significant behavioral questions unanswered.

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 a single, efficient sentence that immediately communicates the core functionality. Every word earns its place: 'Get' establishes the action, 'PayFast transaction history' specifies the resource, and 'optional date range and pagination' highlights key capabilities. There's no wasted verbiage or unnecessary elaboration.

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 operation with 4 well-documented parameters in the schema, the description provides adequate but minimal context. The lack of output schema means the description should ideally describe return values, but it doesn't. With no annotations to provide behavioral context and no output schema, the description leaves gaps about what the tool actually returns and under what conditions it operates.

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?

The description mentions 'optional date range and pagination' which maps to the from/to and offset/limit parameters respectively. However, with 100% schema description coverage where each parameter already has clear documentation in the schema, the description adds minimal value beyond what's already structured. The baseline score of 3 reflects adequate but not exceptional parameter guidance given the comprehensive schema.

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 verb ('Get') and resource ('PayFast transaction history'), making the purpose immediately understandable. It distinguishes this tool from siblings like transaction.charge (which creates transactions) and transaction.fetch (which likely retrieves a single transaction). However, it doesn't explicitly differentiate from refund.query or subscription.fetch, which might also retrieve historical data.

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 mentions 'optional date range and pagination' which provides some context about when to use parameters, but offers no guidance on when to choose this tool versus alternatives like transaction.fetch (for single transactions) or refund.query (for refund history). There's no mention of prerequisites, authentication requirements, or typical use cases.

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