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

Given no annotations, the description carries the behavioral burden. It discloses the primary side effect (ends the session) and the precondition. It does not explicitly state irreversibility or what occurs if the condition isn't met, but for a simple action, the main behaviors are transparent.

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?

Two sentences, front-loaded with the action, and every word earns its place. No fluff or redundancy.

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 simple finalization tool with one parameter and no output schema, the description is sufficiently complete: it states what it does, the side effect, and the precondition. Could elaborate on 'progress' or error handling, but that's not essential given the context.

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% for the sole parameter (session_id), which is already explained as 'Session id returned by start_session.' The tool description adds no additional meaning beyond the schema, so baseline 3 is appropriate.

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 a specific verb+resource: 'Reveal the hidden solution and end the session.' This distinguishes it from sibling tools (ask_question, start_session) as the final action that reveals the answer and terminates the session.

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?

Provides a clear condition for use ('Only allowed once solve progress reaches 60'), implying it should be used when the session has progressed sufficiently and the user wants to end. It does not explicitly mention alternatives or when not to use, but the constraint gives clear situational context.

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