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

With no annotations, the description carries the full burden, and it does disclose one important side effect: the candidate list is cleared. It does not say whether the accepted scene is appended or replaces anything, whether the operation is reversible (storyline.rewind exists but is not referenced), or what the response contains.

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?

Two short sentences, front-loaded with the core action and followed by the side-effect warning. No filler or redundancy.

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 mutation tool with no annotations, no output schema, and a nested edits object with zero field documentation, the description is too thin. An agent cannot tell what the edits fields do, what happens to the storyline on success, or how to recover from a mistaken pick.

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 0% across three parameters, including a nested 'edits' object with seven undocumented fields. The description only says 'optionally with edits' and never explains what can be edited or how edits interact with the candidate, so it fails to compensate for the schema gap.

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 gives a specific verb ('Accept') and resource ('one of the current candidates as the next scene in the storyline'), which is far more informative than the bare name storyline.pick. It implicitly distinguishes itself from storyline.set_candidates and storyline.suggest by operating on already-existing candidates, though it never names those siblings explicitly.

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 phrase 'Clears the candidates — suggest new ones afterwards' implies the tool is used at the point of choosing among existing candidates and points to a follow-up action. However, it never states prerequisites (candidates must exist), nor does it explicitly contrast with storyline.suggest or storyline.set_candidates, leaving the agent to infer the workflow.

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