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

The description provides rich behavioral detail about optimistic concurrency, partial updates, null semantics, and the OUT_OF_SYNC failure mode. However, it contradicts the annotation idempotentHint=true: a successful update changes updatedAt, so a second identical call with the same baseUpdatedAt would fail. This annotation contradiction is a significant reliability issue.

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 dense but every clause earns its place. It front-loads the purpose incorrectly? Actually it front-loads resource and fields, then adds only necessary behavioral notes. There is no filler.

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 input schema parameters list, the description covers all relevant aspects: authorization, partial update behavior, concurrency requirement, failure mode, and special null/array semantics. Output schema exists, so return-format details are not required.

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 zero properties, yet the description fully documents the intended parameters: name, description, number, date, order, sessionId, parentId, and playerIds. It enriches each with domain-specific meaning, including null-detach behavior and the [] reopens-to-everyone semantics.

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 opens with a specific verb and resource, 'Update a move by id', and then enumerates the editable fields with precise semantics. This clearly distinguishes it from sibling tools like play_update_page or play_update_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?

It explicitly says this is GM-onlybool, explains that only supplied fields are sent, and mandates a fresh play_get_move read to obtain baseUpdatedAt. It does not explicitly compare against alternatives such as play_create_move or play_delete_move, but the usage context is clear.

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