Happy Server MCP

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 discloses that the tool waits for a session to become idle, implying it blocks until processing finishes or times out. However, it doesn't detail behavioral traits like error handling, what 'idle' means precisely, or side effects (e.g., if it consumes resources). This is adequate but has gaps for a tool with no annotation coverage.

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 front-loaded and efficient: two sentences that directly explain the purpose and usage without waste. Every sentence earns its place by providing essential information, making it appropriately sized for the tool's complexity.

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 no annotations, no output schema, and 2 parameters with full schema coverage, the description is minimally complete. It covers the basic purpose and usage but lacks details on return values, error cases, or deeper behavioral context. For a wait tool with no structured output, this is adequate but not thorough.

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 both parameters ('session_id' and 'timeout_seconds') with descriptions. The description adds no additional meaning beyond what the schema provides, such as clarifying parameter interactions or usage tips. Baseline 3 is appropriate when the 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 clearly states the tool's purpose: 'Wait for a Happy AI session to become idle (finish processing).' It specifies the verb ('wait for') and resource ('Happy AI session'), making it understandable. However, it doesn't explicitly differentiate from siblings like 'happy_read_messages' or 'happy_send_message' in terms of timing or state management, which prevents a perfect score.

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 clear context on when to use it: 'Useful after sending a message to wait for AI to complete its work.' This gives a specific scenario (post-message) but doesn't mention alternatives (e.g., polling with other tools) or exclusions (e.g., when not to wait), so it's not fully comprehensive.

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