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

With no annotations, the description carries the full burden and does well: it discloses the 10-minute duration, that it returns the first item and the deadline, that auth is a NIP-98 signed event for POST /api/games/<game>/start, and that the body is empty. It does not cover repeated-start/idempotency or rate limits.

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?

A single dense sentence front-loads the purpose, then appends the auth/transport detail. Efficient and free of filler, though the auth clause is somewhat compressed and reads densely.

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 tool with no output schema, the description covers what an agent needs: the action, the auth requirement, the empty body, and a partial description of the return (first item + deadline). Only the 'format' parameter and repeat-invocation behavior are left unaddressed.

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 coverage is 75%, so the schema already documents auth, body, and format. The description restates the game enum values and the empty-body requirement but adds little new meaning, and never explains the 'format' parameter. 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?

States a specific verb+resource ('Start a ... game run') and enumerates the three game modes, so the agent knows exactly what action is being triggered. It does not explicitly contrast itself with siblings like game_answer or game_board, so it falls short of a 5.

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 the usage context (kicking off a run) and adds a practical constraint ('empty body'), but offers no explicit when-not-to-use guidance or reference to the answering/board siblings that follow a start. Adequate but with clear gaps.

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