JuliusBrussee/caveman · error · Error

${agent} ${serverName} MCP rollback postflight mismatch

Error message

${agent} ${serverName} MCP rollback postflight mismatch

What it means

Postflight verification after rolling back an interrupted MCP transaction: the config and ownership journal state on disk does not match what the rollback expected to produce. The recovery itself hit an inconsistency (concurrent modification or lost writes), so the mismatch is surfaced instead of being silently ignored.

Source

Thrown at packages/cli/src/index.ts:12490

    process.stderr.write(`${mark("warn")} discarded uncommitted ${agent} ${serverName} MCP transaction\n`);
    return "discarded";
  }
  if ((!configIsBefore && !configIsAfter) || (!markerIsBefore && !markerIsAfter)) {
    throw new Error(`${agent} ${serverName} MCP config or ownership journal changed during interrupted transaction; refusing destructive recovery`);
  }
  if (!configPending || !locatorPending) {
    throw new Error(`${agent} ${serverName} MCP transaction lost one durable journal copy; refusing destructive recovery`);
  }

  if (!configIsBefore) {
    durableReplaceFileIfUnchanged(configPath, configCurrent, configBefore, journal.config_before_mode);
  }
  if (!markerIsBefore) {
    durableReplaceFileIfUnchanged(markerPath, markerCurrent, markerBefore, journal.marker_before_mode);
  }
  if (optionalBytesHash(fileBytes(configPath)) !== journal.config_before_sha256
    || optionalBytesHash(fileBytes(markerPath)) !== journal.marker_before_sha256) {
    throw new Error(`${agent} ${serverName} MCP rollback postflight mismatch`);
  }
  removePendingCopies();
  process.stderr.write(`${mark("warn")} rolled back interrupted ${agent} ${serverName} MCP transaction\n`);
  return "rolled-back";
}

function transactOwnedMcpConfig(
  agent: "kilo" | "qwen",
  serverName: string,
  action: "install" | "uninstall",
  mcp?: { command: string; args: string[] },
  lockedConfigPath?: string,
): boolean {
  const plan = action === "install"
    ? agent === "kilo" ? planMcpKiloJson(mcp!, serverName) : planMcpQwenJson(mcp!, serverName)
    : agent === "kilo" ? planRemoveMcpKiloJson(serverName) : planRemoveMcpQwenJson(serverName);
  if (!plan) return false;
  if (lockedConfigPath && plan.path !== canonicalMcpConfigPath(lockedConfigPath)) {

View on GitHub (pinned to 5184b3d11a)

Solutions

1. Manually compare the config file and ownership marker against the journal's before hashes and restore the intended state
2. Delete the journal and marker and re-run the managed MCP install to rebuild a clean owned state
3. Prevent concurrent edits to the MCP config while transactions are recovering

When it happens

Trigger: Thrown at packages/cli/src/index.ts:12490 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of JuliusBrussee/caveman@5184b3d11a (2026-09-06). Data as JSON: /api/errors/fb743f2ce580058f. Report an issue: GitHub.