Threads MCP Server

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

With no annotations provided, the description carries full burden but only states it 'lists threads with optional filtering'. It doesn't disclose whether this is a read-only operation, pagination behavior, rate limits, authentication requirements, or what happens when no filters are applied. For a tool with 8 parameters and no annotation coverage, this is inadequate behavioral disclosure.

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 waste. It's appropriately sized and front-loaded with the core purpose. Every word earns its place without redundancy 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 tool with 8 parameters, no annotations, and no output schema, the description is incomplete. It doesn't explain what 'threads' are in this context, what the return format looks like, or how filtering logic works (AND/OR). The agent lacks sufficient context to use this tool effectively despite the comprehensive schema.

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 already documents all 8 parameters thoroughly with descriptions and enum values. The description adds no additional parameter semantics beyond mentioning 'optional filtering', which is already evident from 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 'List threads with optional filtering' clearly states the verb ('list') and resource ('threads'), but it's vague about scope and doesn't distinguish from sibling tools like 'search_threads' or 'get_thread'. It provides basic purpose but lacks specificity about what kind of threads or system context.

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 'search_threads' or 'get_thread'. There's no mention of prerequisites, typical use cases, or when not to use it. The agent must infer usage from the tool name alone.

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