postfast-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 mentions generating a link but doesn't cover key traits like whether this action is idempotent, requires authentication, has rate limits, or what happens on failure (e.g., if email sending fails). This leaves significant gaps for a tool that likely involves external interactions.

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 directly states the tool's purpose without unnecessary words. It's front-loaded with the core action and outcome, making it easy to parse and understand quickly.

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?

Given the complexity of generating external links (which may involve security, expiration, and email delivery), the lack of annotations and output schema means the description should do more. It doesn't explain the return value (e.g., link format, success indicators) or error conditions, making it incomplete for safe and effective use by an agent.

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 input schema has 100% description coverage, detailing all three parameters (expiryDays, sendEmail, email) with defaults and constraints. The description adds no additional parameter semantics beyond what's in the schema, such as explaining the link format or email content, so it meets the baseline score without compensating value.

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 ('generate a shareable link') and the purpose ('for external clients to connect their social accounts to the workspace'), which is specific and actionable. However, it doesn't explicitly differentiate from sibling tools like 'list_accounts' or 'get_upload_urls', which might involve account management or sharing, so it doesn't reach the highest score.

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, such as whether it's for onboarding new clients or reconnecting existing ones. It also doesn't mention prerequisites, like needing workspace access or specific permissions, leaving the agent with no contextual cues for selection.

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