Enable AGY for one project

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

Annotations already convey readOnly=false, idempotentHint=true, and destructiveHint=false. The description adds useful behavioral context beyond those: the operation is atomic, scoped to exactly one root, and 'Does not call a model.' This helps the agent understand side effects and execution characteristics.

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 two sentences, front-loaded with the core action, and every clause adds value: initialization, atomicity, scoping, user-consent precondition, and the no-model-call note. No filler or repetition.

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 single-parameter tool with no output schema, the description covers purpose, scope, precondition, and behavioral nuances. It does not describe return values or failure modes, but the annotations and simple schema make this adequate. Overall it is complete enough for safe 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%: project_root is documented as 'Absolute root directory of the current Codex project.' The description adds the qualifier 'exact project root' but does not substantially extend the schema's parameter meaning. Baseline 3 is appropriate because the schema carries the semantic weight.

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 uses specific verbs and resources: 'Initialize .antigravity-mcp' and 'add only that root to Antigravity trustedWorkspaces and read_file allow rules.' It clearly distinguishes this enable operation from sibling tools like antigravity_disable_project and project status tools.

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 precondition: 'Call only after the user explicitly requests AGY.' It also clarifies scope with 'one exact project root' and 'only that root,' giving clear context for when to invoke it. It does not explicitly mention alternatives, but the enabling-vs-disabling contrast with siblings is implied.

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