opencode_launch_ui

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

Only readOnlyHint=false is declared, so the description must carry behavioral weight. It usefully documents the return payload and the three modes, but omits key traits: whether the call blocks until the UI exits, what happens if a UI/server is already running, and what the 'serve' background mode implies for later shutdown (a sibling opencode_shutdown exists but isn't referenced).

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?

Front-loaded purpose sentence, then compact Return Format and Examples sections. Slightly more scaffolding than a 2-parameter tool strictly needs, but nothing is wasted or buried.

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?

No output schema exists, so the explicit Return Format block is valuable and covers the return contract. The remaining gap is lifecycle behavior (blocking, re-launch, pairing with opencode_shutdown), which matters for a tool that starts long-lived processes.

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% with an enum on mode and a documented default, so the schema already does the heavy lifting. The two examples (mode="web", mode="serve") show call shape but add no semantic detail beyond the enum descriptions, so 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 (launch) and resource (opencode interface) plus three distinct modes (TUI, web UI, background API server). It is clearly distinct from the sibling tools, which manage sessions/runs/config, though it doesn't explicitly name a sibling to contrast against.

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?

'Use this to open the opencode interface for manual work' implies the context (interactive/manual use vs. the programmatic run/agent tools), but there is no explicit when-not guidance, no mention of conflicts with running instances, and no named alternative to route to instead.

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