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

Annotations already declare readOnly, idempotent, non-destructive, closed-world, so safety is covered; the description adds the return shape (title, target_seconds, target_words, aspect_ratio, presenter, subtitle_style, has_script, scenes, script_seconds), which is valuable since there is no output schema. It does not mention auth/prerequisite details, but little more is needed for a pure read.

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 verb and purpose, then usage, then return fields, with no filler. The first sentence's long enumerated clause ('who presents it and in what subtitle style, who it is for and how it should sound') is slightly dense but every phrase maps to an actual returned field.

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 explicit return-field list is exactly what an agent needs to decide whether this call supplies the data it wants; the use/avoid guidance and sibling references round out the picture. Nothing an agent needs to invoke 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?

Only one parameter (project_id) with 100% schema description coverage ('from list_projects'), so the schema already carries the meaning fully. The description adds no further semantics about the identifier's form or lookup, which is the expected baseline when schema coverage is complete.

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?

Opens with a specific verb+resource ('[read] Read this project') and immediately enumerates the concrete fields it exposes (title, target length, aspect ratio, presenter, subtitle style, audience/tone, has_script). It further differentiates scope by stating what it is NOT for and naming the alternative (get_video_assets_state).

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?

'Use when starting on a talking project's script, to write to the right length and shape' gives an explicit trigger condition, and 'Not for the board's scenes and assets (use get_video_assets_state)' gives an explicit exclusion plus the replacement tool. Related tools (read_script, write_script, set_length) are named for workflow routing.

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