Execute a coding task with OpenCode

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

The description adds meaningful behavior over the annotations (destructiveHint=true, readOnlyHint=false) by disclosing non-interactive execution, possible file modifications, CLI/Git actions, and execution of tests. It also warns that the returned Git diff is a post-run snapshot and may include pre-existing changes. This is useful, though it does not enumerate every destructive action or limitation.

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 focused: one purpose-driven opening sentence followed by a terse but information-dense paragraph about behavior and result shape. Every sentence earns its place, including the important Git-diff caveat. The length is appropriate for the tool's complexity.

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?

With a complete input schema and an output schema present, the description covers the main operational ambiguity: non-interactive execution, mutation of files, and the non-isolated nature of the Git diff. It is mostly complete, but it leaves the distinction versus opencode_check unstated, and it does not describe interaction between the timeout/model parameters and the result.

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 coverage is 100%, so the parameter descriptions in the schema already carry the meaning for task, working_directory, model, timeout, and reasoning_effort. The tool description does not add extra parameter syntax, examples, or semantic clarifications 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 immediately states a specific operation: delegating one repository coding task to OpenCode, and enumerates what the tool can do (read/modify files, run commands, tests, Git). It is clear, but it does not explicitly contrast with the sibling tool opencode_check, so it stops short of full differentiation.

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 first sentence implies the usage: delegate a coding task to OpenCode. The description also clarifies that it runs non-interactively in a repository, which helps the agent set expectations. However, there is no explicit 'when not to use' or comparison with the sibling opencode_check; usage guidance is present but largely implicit.

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