opencode-consistent

OpenCode rebuilds the system prompt on every turn. In 1.18.27 the <env> block is cwd, worktree, git yes/no, platform, and Today's date: ${new Date().toDateString()}. Prefix caches hash from token 0, so when the calendar rolls the whole session misses.

AGENTS.md, MCP instructions, and the skill list are re-read from disk. If you did not edit them, a restart already sends the same bytes. This plugin does not freeze those, so a mid-session edit still reaches the model (and correctly misses the old prefix).

The other restart miss is MCP tools, which are not in the system string. They sit after the built-in tool schemas. If those servers are still connecting, vLLM hashes builtins only (1,792 tokens = 7×256 blocks) and prefills the rest.

This plugin:

1. Pins Today's date on the first real turn of a sessionID and rewrites just that field later, including after quit/reopen.
2. Waits in chat.message until the same MCP servers are connected (or have finished failing) so SessionTools.resolve includes the same tool block.

Upstream: #32622 (date in the cached prefix, closed not-planned), #29672, PR #29949 (move env to the tail, not default as of 1.18.27).

Install

Put it last in the plugin list:

{
  "plugin": [
    "opencode-consistent"
  ]
}

Optional wait budget (milliseconds). Default 15000. 0 polls once and does not block.

{
  "plugin": [
    ["opencode-consistent", { "mcpWaitMs": 20000 }]
  ]
}

Same value via OPENCODE_CONSISTENT_MCP_WAIT_MS. Restart OpenCode. Plugins load at process start.

What it freezes

Today's date per sessionID, on disk under ~/.local/state/opencode/consistent/.

The list of MCP server names that were connected when that date was first pinned. Later turns wait until those names are connected again.

Title-generation has no date line. Those calls are ignored.

What it does not freeze

AGENTS.md, cwd, skills, MCP instruction prose. Change them and the next turn is live — and a new prefix hash.

Tool JSON schemas. The plugin cannot inject a missing MCP tool. If a server is still down after mcpWaitMs, or it advertises different tools, the hash still misses after the built-in set.

/compact still rewrites history.

Debug

OPENCODE_CONSISTENT_LOG=1 opencode

Writes ~/.local/state/opencode/opencode-consistent.log with wait ok|timeout and snapshot / restore date=…. Restore keeps the first-turn date; sha= of the full system string is allowed to move when AGENTS.md or skills change.

License

MIT