restore_version

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

With no annotations, the description carries the full burden and does so: immediate takeover without stopping playback, non-destructive history append ("restored from #id", nothing rewritten), replacement of a pending bar/phrase-line change, Moontide auto-start only for ids that exist, and the return value being the page-confirmed code. These are exactly the mutation semantics an agent cannot infer from the schema.

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?

Front-loaded with the core action and the key routing rule, and most sentences carry distinct information. There is mild redundancy around immediate takeover ("within a fraction of a second", "always takes over at once", "replaces the music at once") that could be consolidated.

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 two-parameter mutation tool with no annotations and no output schema, the description covers safety (non-destructive history append), timing (instant takeover), side effects (replaces pending queued changes, may start Moontide), and the return value. Nothing an agent needs in order to call it correctly is missing.

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 100%, so both parameters are already documented, including the answering request-line field. The description reinforces the id's origin and adds the constraint that the id must exist in history, but adds little beyond the schema text, so the baseline of 3 applies.

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 and resource — plays a past version again by its id from list_history — and makes the boundary with set_code and list_history explicit. An agent can distinguish this from edit_code, set_code, and favorite_version without opening any schema.

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?

Gives an explicit when-not: if the user asked for gradual changes this session, use set_code with a transition instead. It also names list_history as the source of the id and notes the shared checks with set_code, so the routing decision is fully determined.

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