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

Annotations already cover safety (readOnly, non-destructive, closed-world), but the description adds the important behavioral caveat that the project may have been changed elsewhere and must be re-read before editing. With no output schema, the detailed inventory of returned fields also carries real disclosure weight.

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 core action and self-contained in two sentences. The long enumeration of returned sections is dense but functional in the absence of an output schema, though it reads as a list rather than a structured breakdown.

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 read-only, single-parameter tool with no output schema, the description covers what is returned, why callers need it, and a caveat about stale data. Nothing needed 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?

There is one parameter at 100% schema coverage; the schema already explains that projectId comes from list_projects or create_project. The description adds no extra meaning such as format, validation, or error behavior for the id. Baseline 3 applies when the schema does the work.

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 ("Read a whole project as JSON") and immediately enumerates what is covered: name/details, voiceover, voices, canvas, tracks, timeline blocks, animations, styles, variables, and storage files. That scope distinguishes it from siblings like read_video_guide and edit_project without needing their schemas.

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 explicit workflow guidance: "Read it before editing, since the user may have changed it in the Studio." This tells the agent when to call it and why freshness matters. It stops short of naming an alternative to use instead of or alongside it, keeping it below a 5.

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