postfast-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. It mentions optional filters but doesn't describe pagination behavior (implied by 'page' and 'limit' parameters), rate limits, authentication requirements, or what happens when no filters are applied. For a list operation with 6 parameters, this leaves significant gaps in understanding how the tool behaves.

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 front-loads the core purpose and mentions key filter categories. Every word earns its place with zero waste or redundancy. It's appropriately sized for a list operation with clear parameters.

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 list tool with 6 well-documented parameters but no annotations or output schema, the description provides basic purpose but lacks behavioral context. It doesn't explain pagination mechanics, response format, error conditions, or how filters interact. While the schema covers parameter details, the description should compensate for missing annotations by describing operational behavior.

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 fully documents all 6 parameters with their types, constraints, and formats. The description adds marginal value by naming three filter categories ('platform, status, and date range') which map to parameters, but doesn't provide additional semantic context beyond what's already in the schema. Baseline 3 is appropriate when schema does the heavy lifting.

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 ('List') and resource ('social media posts') with specific optional filters mentioned. It distinguishes this tool from siblings like 'create_posts' or 'delete_post' by focusing on retrieval rather than mutation. However, it doesn't explicitly differentiate from other list tools like 'list_accounts' beyond the resource type.

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 like 'list_accounts' or 'get_post_analytics'. It mentions optional filters but doesn't explain scenarios where filtering is appropriate or when to prefer this over other tools. No prerequisites, exclusions, or sibling comparisons are included.

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