Resume a subagent

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

With no annotations provided, the description carries the behavioral burden. It discloses persistence across bridge restarts and idempotent no-op behavior, which are important and non-obvious. It does not mention error behavior for unknown names, but the core invocation behavior is well covered.

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 a single focused sentence with no filler. The core purpose is front-loaded, and the two caveats about persistence and no-op behavior are concise and high-value.

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 one-parameter tool with a complete schema, the description covers the essential invocation context. Minor gaps include lack of detail about return values or behavior when the named subagent does not exist, but these are not critical for basic correct use.

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 single required parameter is already fully documented. The description adds no additional parameter semantics, and none are needed beyond what the schema provides.

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 states a clear verb, 'Re-activate', and a specific resource, 'stopped/dead/persisted Devin session'. It also distinguishes itself from lifecycle siblings by noting it survives bridge restarts and is a no-op on running subagents.

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 clearly implies when to use it: for sessions that are stopped, dead, or persisted. It also provides an explicit when-not condition by stating it is a safe no-op on already-running subagents, though it does not name alternative tools like spawn.

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