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

Annotations already declare destructiveHint=true, idempotentHint=true, and openWorldHint=true, so the description only needs to add context beyond that. It does: the Series-ownership prerequisite, the fact that omitted runtime/models inherit Series defaults, that board options default off, and that canon and episode slots are preserved. It does not say what happens to an existing episode slot or whether repeated calls with the same request_key dedupe, which would have pushed it higher.

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?

Roughly six dense sentences, each carrying a distinct constraint, with no filler. The ordering is slightly awkward, since field-authoring guidance for description and source_document_ids arrives before the reader has anchored on what the call creates, and the phrase "Description is the complete creator-facing creative Project Brief" momentarily reads as if it describes the tool rather than a parameter.

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?

An output schema exists, so return values need no coverage, and settings are heavily documented in the schema. But this is a complex, destructive, nested-object creation tool, and the description leaves the inheritance_mode/inheritance_profile semantics and the interaction between season_id and episode_number entirely to inference.

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 50%, and the two empty-description fields (name, description) are given real meaning: the description must be the creator-facing creative brief with Markdown headings and paced outline, and must exclude execution instructions, status, and provenance. source_document_ids is explained as live document links rather than provenance text, and the description steers runtime/settings/placement into their own fields. The inheritance_mode and inheritance_profile enums (snapshot vs live, full vs selected vs style_only) receive no explanation anywhere, which is the main 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 first sentence states a specific verb and resource ("Create a Film Studio project") and adds a scoping clause ("without starting chat or media"). That separates it from chat/chat-start tools, but it does not distinguish itself from the similarly named siblings create_film_project or native.create_series_project, leaving the agent to infer which creator applies.

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 supplies a prerequisite ("Requires Series ownership") and one exclusion (no chat or media start), which implies when to use it. However, it never names an alternative such as create_season, native.create_film_project, or the work-start tools, so the agent has no explicit routing rule when several create paths are viable.

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