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

Beyond the annotations, it discloses partial-update semantics ('Only the fields given change'), the saved-render prerequisite for public visibility, deferred rendering of style changes, and what public means (share page and public GLB URL for meshes). None of this contradicts the annotations.

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?

The description is long because the tool has 14 parameters, but every sentence carries information and the operative 'Use when...' clause is front-loaded. The later exclusions and constraints are grouped logically and not redundant with the schema.

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 high-complexity update tool, it covers prerequisites, side-effect timing, alternatives, and field applicability. Since an output schema exists, the absence of return-value detail is acceptable; nothing needed to call 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?

With 79% schema coverage, the description still adds project-type scoping: which fields apply to logo/coin vs text projects, and it labels coin-only fields (look, coin/mark colours, blank edge). It also clarifies that only provided fields change, giving the parameter set a meaningful update model.

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 description opens with a specific verb and resource — changing an existing project without opening the studio — and enumerates the updateable fields (title, public flag, style, text, coin options). It also names sibling tools it is not (create_share_link, create_text_logo_project, duplicate_project), so an agent can distinguish it clearly.

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 explicitly states the condition for use ('when the user wants an existing project changed without opening the studio') and gives exclusions with named alternatives. It also adds task-specific prerequisites: making a project public needs a saved render and style changes render only on next open-and-save.

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