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

Adds substantial context beyond the annotations: the paid nature, the recipe-style output with exact files and paths, dependency install line, ordered steps, and verification behavior. This fully discloses what the agent should expect without contradicting readOnlyHint or idempotentHint.

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 sentences, each carrying distinct information: paid status, core purpose, return format, and prerequisite. It is dense and front-loaded with the most important facts, with no filler.

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 tool with no output schema, the description explains the generated recipe, file targeting, dependency installation, and how verify_app relates. The only notable gap is not explicitly separating this from emit_screen, but the whole-app scope is sufficiently clear for correct invocation.

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 description coverage is 100%, so the baseline of 3 applies. The description only reiterates that appId is the share code, which the schema already says, and adds no new meaning for the override parameter.

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 a specific action and resource: it turns an opointo canvas into a working Expo app, with concrete deliverables. It does not explicitly contrast itself with sibling emit_screen, but the whole-app scope is clear from the title and description.

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?

The description gives important preconditions: it is paid and requires a share code from the App Builder. However, it never explicitly states when to use this tool versus emit_screen or add_screen, so usage guidance is mostly implied rather than directly stated.

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