Happy Server MCP

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

With no annotations provided, the description carries full burden for behavioral disclosure. It states the session will be 'terminated and marked as inactive,' which implies a destructive, irreversible action, but does not cover critical details like required permissions, side effects (e.g., data loss), error conditions, or response format. This leaves significant gaps for a mutation tool.

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 two concise sentences with zero waste. The first sentence states the action and resource, and the second clarifies the outcome. It is front-loaded and appropriately sized for the tool's complexity, earning its place efficiently.

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 destructive nature (implied by 'terminated'), lack of annotations, and no output schema, the description is incomplete. It fails to address permissions, reversibility, error handling, or return values, which are critical for safe and effective use. The description does not compensate for the missing structured data.

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 the single parameter (session_id). The description does not add any parameter-specific details beyond what the schema provides, but with only one parameter, the baseline is high. No extra semantic context is given, but the minimal parameter count reduces the need for compensation.

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 action ('Archive (stop)') and resource ('a Happy AI session'), distinguishing it from siblings like happy_list_sessions (list) and happy_start_session (create). The parenthetical 'stop' reinforces the termination action, making the purpose specific 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 implies usage when a session should be terminated and marked inactive, but lacks explicit guidance on when to use this versus alternatives (e.g., happy_wait_for_idle for pausing, or happy_zen_link_session for linking). No exclusions or prerequisites are mentioned, leaving usage context partially implied rather than fully articulated.

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