Continue Antigravity

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

Annotations already mark the tool as destructive, non-idempotent, and openWorld. The description adds meaningful behavioral context beyond those flags: parallel runs with distinct IDs, BUSY on simultaneous continuations, exclusive server access when no ID is given, and the risk of external CLI sessions altering the latest conversation. This is valuable operational transparency.

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, all dense with relevant information: purpose, concurrency semantics, failure conditions, external-state caveat, and workspace requirement. No filler or redundant restatement of the name or annotations.

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 an 8-parameter mutating tool with no output schema, the description covers key operational constraints: conversation ID handling, BUSY states, workspace reuse, and external session effects. It does not describe return values or explicitly compare against antigravity_run, but the schema and annotations fill most remaining gaps.

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?

The schema covers 75% of parameters with descriptions, and the description adds semantics for conversation_id (omitting it resumes the latest conversation, with parallelism and BUSY behavior) and workspace (must match the original turn). Some parameters like effort remain undocumented in the description, but the schema enums partially compensate.

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 'Follow up in an existing Antigravity conversation,' which states a specific verb, resource, and scope. The focus on 'existing conversation' and 'continuations' clearly differentiates this from the sibling 'antigravity_run' without requiring the agent to open either schema.

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 clear conditions for when to use explicit conversation_ids versus relying on the latest conversation, including BUSY risk and the warning that other CLI sessions may change the latest conversation. It also instructs to use the same workspace as the original turn, but it does not explicitly name antigravity_run as the alternative for starting a new conversation.

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