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

Annotations already declare readOnly/destructive=false, but the description adds crucial context beyond them: it returns source files for local rendering, the project document is caller-held and must be kept for later calls, it must not be described as a hosted saved project, and non-copy edits cannot be preserved across a switch.

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 purpose and alternative, and every sentence encodes a rule rather than filler. It is dense and somewhat run-on with many clauses packed together, which slightly reduces readability.

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 5-param nested-object tool with no output schema, the description covers the caller-held lifecycle, framework selection, revision checking, edit ordering, and the return of source files — everything an agent needs to call it correctly.

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 parameters are documented structurally. The description still adds meaning beyond the schema: framework omission/'no-preference' semantics, expectedRevision checking the supplied document rather than a server version, and the ordering rule for edits.

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?

States specific verbs (prepare, continue, edit, switch) plus the resource (announcement-card-v1 template / caller-held project). Explicitly distinguishes itself from prepare_video_template, which it names as the tool for VideoSpec templates in either framework.

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 routing rules: use this for paired announcement-card-v1 or HyperFrames announcement requests, use prepare_video_template for VideoSpec. Adds decision guidance — never infer framework from creative wording, omit framework unless explicitly chosen, ask the user on needs-selection, apply edits before switching.

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