set_active_session

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

No annotations are provided, so the description carries the full burden. It states the tool sets an active session but doesn't disclose behavioral traits like whether this requires specific permissions, if changes are reversible, what happens if the session_id is invalid, or if there are rate limits. For a mutation tool with zero annotation coverage, this is a significant gap.

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 ('Set which debug session should be the active/default session') and adds necessary context ('for subsequent commands'). There is zero waste, making it highly concise and well-structured.

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 tool's moderate complexity (a mutation operation with no annotations or output schema), the description is minimally adequate. It explains what the tool does but lacks details on behavioral aspects, error handling, or return values. With no output schema, the description should ideally hint at what to expect after invocation, but it doesn't.

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, with the single parameter 'session_id' clearly documented. The description adds no additional parameter semantics beyond what the schema provides, but with high schema coverage and only one parameter, the baseline is appropriately high. No compensation is needed.

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 ('Set') and the target resource ('which debug session should be the active/default session'), distinguishing it from sibling tools like 'list_sessions' or 'close_session'. It precisely defines the tool's function without being tautological.

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 implies usage context by mentioning 'subsequent commands', suggesting this tool sets a default for follow-up operations. However, it lacks explicit guidance on when to use it versus alternatives (e.g., 'list_sessions' to see available sessions) or prerequisites (e.g., requiring an existing session).

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