Pararam Nexus MCP

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

With no annotations provided, the description carries the full burden and does well by disclosing multiple behavioral aspects: the dual-mode operation (save to disk vs. direct display), supported file types for display, different return types based on conditions, and error handling. It doesn't mention rate limits, authentication needs, or file size limits, but covers the core operational behavior thoroughly.

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 well-structured with clear sections for behavior, supported types, arguments, and returns. Every sentence adds value, though the supported file types list is quite detailed. It's appropriately sized for a tool with complex conditional behavior, though could be slightly more concise in the file types enumeration.

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 tool with 4 parameters, 0% schema coverage, no annotations, and no output schema, the description does an excellent job covering the essential context: purpose, parameter semantics, behavioral logic, and return types. The main gap is lack of information about authentication requirements, rate limits, or error specifics beyond mentioning error responses exist.

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?

With 0% schema description coverage for 4 parameters, the description compensates excellently by explaining the semantics of 'output_path' in detail (including the None case implications) and clarifying that 'file_guid' comes 'from get_post_attachments'. It provides crucial context about how parameters affect behavior that the bare schema cannot convey.

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 specific action ('Download a specific attachment from a post') with the resource identified. It distinguishes this tool from siblings like 'get_post_attachments' (which lists attachments) and 'upload_file_to_chat' (which uploads rather than downloads). The verb+resource combination is precise and unambiguous.

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 clear context about when to use different output modes based on 'output_path' parameter and file type support. However, it doesn't explicitly state when to use this tool versus alternatives like 'get_post_attachments' (which might be needed first to obtain file_guid) or mention any prerequisites or exclusions for usage.

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