Update OpenCode settings by submitting a partial config object, with an optional project directory to apply changes to.
Update the opencode configuration. Pass a partial config object.
| Name | Required | Description | Default |
|---|---|---|---|
| config | Yes | Partial config object with fields to update | |
| directory | No | Project directory to target. Optional; defaults to the server default project. |
Changes observed during successful MCP inspections.
v3.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full behavioral burden. 'Partial config object' hints at merge semantics, which is a genuinely valuable signal, but nothing is said about persistence (disk vs in-memory), whether a restart/take-effect is required, permissions, reversibility, or how nested fields are treated on merge — all critical for a mutation tool targeting a nested config.
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 short sentences, front-loaded with the action, and no filler. It is efficient, though its brevity for a nested-object mutation tool edges toward under-specification rather than deliberate conciseness.
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 mutation tool with no annotations, no output schema, and a nested-object parameter, the description should explain merge-vs-replace behavior and whether changes persist. With only 'pass a partial config object', the agent lacks enough to call it confidently and predict the effect.
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 both parameters and their meanings are already documented in the schema. The description's phrase 'partial config object' restates the schema's 'Partial config object with fields to update' without adding format or merging depth details, so the baseline 3 applies.
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?
States a specific verb and resource ('Update the opencode configuration') that an agent can read at face value. It does not name or distinguish itself from the sibling opencode_config_get, so differentiation is left to the agent, but the purpose itself is unambiguous.
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?
No when-to-use guidance, no prerequisites, and no mention of opencode_config_get as the read-side counterpart. The agent is told what to pass but not when this tool is the right choice versus reading or restarting.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.