brilliant-directories-mcp

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. 'Add email to unsubscribe list' implies a write/mutation operation but doesn't specify permissions required, whether the operation is idempotent, what happens on duplicate emails, error conditions, or response format. For a mutation tool with zero annotation coverage, this is insufficient behavioral context.

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 with zero wasted words. It's front-loaded with the core purpose and uses clear, direct language. Every word earns its place in conveying the essential function.

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 mutation tool with no annotations, no output schema, and incomplete parameter documentation (50% schema coverage), the description is inadequate. It should explain what 'unsubscribe list' means in this context, what the operation returns, error handling, and implications of the 'definitive' parameter. The current description leaves too many questions unanswered for proper agent usage.

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% (only 'definitive' parameter has a description). The description mentions 'email' but doesn't explain its purpose beyond what's implied by the tool name. It adds minimal value beyond the schema, which already documents the email parameter type/format and the definitive parameter with enum values. Baseline 3 is appropriate given partial schema coverage.

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 'Add email to unsubscribe list' clearly states the action (add) and target resource (email to unsubscribe list). It distinguishes from siblings like 'deleteUnsubscribe' and 'getUnsubscribe' by specifying creation rather than deletion or retrieval. However, it doesn't explicitly differentiate from 'updateUnsubscribe' which might modify existing entries.

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 no guidance on when to use this tool versus alternatives. It doesn't mention when to choose createUnsubscribe over updateUnsubscribe, or whether this should be used instead of deleteUnsubscribe for removing emails. No prerequisites, constraints, or typical use cases are described.

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