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

Annotations already cover readOnly, idempotent, non-destructive and closed-world, so the bar is lower. The description still adds real value: results come back in the user's arranged order, hasReferenceSheet flags existing imagery, and includeDescriptions is disclosed as slower with empty strings for missing text. It does not discuss result set size or pagination behavior.

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?

Four front-loaded sentences with no filler; the ordering guarantee and primary identifier come first, followed by secondary field explanations and then the parameters. The mid-sentence field inventory is dense but each item carries meaning for downstream use.

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?

There is no output schema, and the description compensates by enumerating returned fields, their meanings, and the empty-string convention. Combined with ordering, cross-tool identifier linkage, and both optional parameter behaviors, an agent has everything needed to call and interpret this tool.

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 the baseline is 3; the description goes beyond it by explaining what referenceHandle is for ('write it in a shot's actionText'), what entityId maps to in other tools, and the cost/empty-string semantics of includeDescriptions. Only the kind enum is left to the schema, which fully documents it.

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 and resource ('List the project's story entities') and enumerates the domain subtypes (characters, places, objects), which cleanly separates it from create_entities, list_shots, and list_projects. The ordering guarantee is stated up front, so an agent knows exactly what it is calling.

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 concrete usage instructions: filter with kind, set includeDescriptions only when description text is needed, and cross-references get_scene and get_project_outline for how entityId is consumed downstream. It lacks an explicit 'use X instead when...' exclusion against create_entities, but the read-vs-create split with the sibling is obvious from the name.

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