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

Annotations already cover the safety profile (readOnlyHint, idempotentHint, destructiveHint=false, openWorldHint=false), so the bar is lower. The description adds genuinely new context by noting the call is "Free" (no credit cost) and by disclosing the shape of what comes back, including "beats and the original dialogue" for episode mode.

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 sentences, zero filler. The scope/contents sentence is front-loaded and the parameter behavior follows immediately, with the cost hint appended compactly.

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?

With no output schema, the description compensates by enumerating returned fields for both modes, and annotations handle the safety profile. An agent has enough to decide whether to call it and what it will get back.

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%, so the description must carry the load. It documents the only non-obvious parameter well — episode is 1-based and changes the response from an outline to scene-level beats and dialogue. project_id is left to context ("a Story mode project"), which is a minor residual 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 and resource ("Read the analysed script of a Story mode project") and then enumerates the exact contents returned (title, logline, synopsis, genre/tone, episode outline), which lets an agent separate it from story_get_project, story_get_episode, and story_update_script. The two-mode behavior (full script vs. episode-level scenes) is stated up front.

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 clearly states when to supply the optional parameter: "Pass episode (1-based) to get that episode's scenes with beats and the original dialogue," which tells the agent how to switch modes. It does not name alternative tools for related needs (e.g., story_get_episode) or state exclusions, so it stops short of full routing guidance.

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