extend_sandbox

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

No annotations are provided, so the description carries the full behavioral burden. It discloses the key mutation (extending expiry) and an important constraint (24-hour cap from creation). However, it is ambiguous what happens if the requested additional_minutes would exceed the cap—whether the sandbox is clamped to 24 hours or the call fails—and no response behavior is described.

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?

Two sentences with no wasted words: the primary action is front-loaded, followed by the critical limitation. The use case 'long-running work is not cut off' earns its place by motivating the tool.

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 simple two-parameter tool, the description covers the core purpose and the most important bound. But with no output schema and no annotations, it should specify edge-case behavior when the requested extension would exceed the cap and whether the response contains the new expiry time, leaving an agent uncertain about handled limits.

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 description adds context beyond the schema by explaining why a caller would use additional_minutes and that extension is bounded by the 24-hour lifetime cap. However, it does not clarify how sandbox_id is obtained or precisely how additional_minutes is applied, leaving the undocumented sandbox_id parameter uncovered.

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 specific action and resource: 'Push a sandbox's expiry further out'. This directly distinguishes it from sibling tools like create_sandbox and destroy_sandbox, and the phrase 'so long-running work is not cut off' clarifies its exact purpose.

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 clearly indicates when to use the tool: when long-running work risks being cut off. It also provides an important exclusion: the total lifetime is capped at 24 hours from creation, so the tool cannot be used to extend beyond that bound. It does not explicitly name alternative tools, but the purpose is clear enough.

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