session_info

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

With readOnlyHint=true already declaring safety, the description adds valuable security context beyond the annotation: the token value is never returned, stays out of transcripts by design, and the curl example reads the token from its file. This tells the agent exactly how credentials are handled.

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?

Three tight sentences: first states what the tool provides, second states when to use it, third gives a critical security caveat. Front-loaded and every sentence earns its place.

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?

With no output schema, the description fully covers the return contents (base URL, token location, curl example) and the key operational constraint (token never returned). Nothing an agent needs to call this correctly is missing.

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 tool takes zero parameters, so per the baseline rule this scores 4. The description appropriately does not discuss arguments, and there is nothing for it to clarify beyond the empty schema.

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 specifies exactly what the tool returns—connection details for the REST API, including base URL, token location, and a curl example—and distinguishes it from sibling MCP tools by positioning it as the escape hatch for endpoints the MCP tools don't wrap.

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?

It gives an explicit condition for use: 'Use this when you need an endpoint the MCP tools don't wrap, such as saving a video frame to a file.' The default alternative (MCP tools) is implied, and the example makes the boundary concrete.

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