Pi vs OpenCode

Pi

Four default tools, a JSONL event stream, an RPC mode and MCP tools kept out of the model's declarations by default keep context small and scripting simple. Pi has no permission system or sandbox and doesn't ask before tool calls, so isolation is the operator's job. Version 1.0.0 is dated 1 October 2026.

OpenCode

Runs with no key or account on free OpenCode Zen models. Most permissions default to allow, and SECURITY.md says the permission system is not a sandbox.

Pi

1. Run Pi inside a container or VM for unattended work. It has no sandbox and doesn't ask before running shell commands
2. Use pi --mode json and wait for agent_settled. A failed response doesn't set a nonzero exit code in JSON mode
3. Split the JSONL stream on LF only. Node's readline also splits on U+2028 and U+2029, which are valid inside JSON strings
4. Pass --no-approve or --approve in scripts to make the project trust decision explicit
5. Set PI_TELEMETRY=0 and PI_SKIP_VERSION_CHECK=1, or PI_OFFLINE=1, to stop the default requests to pi.dev

OpenCode

1. Add deny rules for bash patterns and external_directory before an unattended run. Most tools default to allow
2. Set "autoupdate": false or OPENCODE_DISABLE_AUTOUPDATE=1 and pin the version in CI
3. Configure a provider key. With none, prompts go to free Zen models that may train on them
4. Set OPENCODE_SERVER_PASSWORD before opencode serve. Without it the server runs unauthenticated
5. Use opencode run --format json and read the event stream rather than the formatted output