Twining MCP Server

Instructions

Implementation Reference

• src/tools/decision-tools.ts:273-299 (handler)

  Registration of the twining_commits tool which calls engine.getByCommitHash.

  // twining_commits — Query decisions by commit hash
  server.registerTool(
    "twining_commits",
    {
      description:
        "Query decisions by commit hash. Returns all decisions that were linked to a given commit, enabling traceability from code changes back to decision rationale.",
      inputSchema: {
        commit_hash: z
          .string()
          .describe("Git commit hash to look up"),
      },
    },
    async (args) => {
      try {
        const result = await engine.getByCommitHash(args.commit_hash);
        return toolResult(result);
      } catch (e) {
        if (e instanceof TwiningError) {
          return toolError(e.message, e.code);
        }
        return toolError(
          e instanceof Error ? e.message : "Unknown error",
          "INTERNAL_ERROR",
        );
      }
    },
  );

• src/engine/decisions.ts:372-397 (handler)

  The implementation of getByCommitHash in DecisionEngine which executes the logic for twining_commits.

   * Get decisions linked to a specific commit hash.
   */
  async getByCommitHash(commitHash: string): Promise<{
    decisions: Array<{
      id: string;
      summary: string;
      domain: string;
      scope: string;
      confidence: string;
      timestamp: string;
      commit_hashes: string[];
    }>;
  }> {
    const decisions = await this.decisionStore.getByCommitHash(commitHash);
    return {
      decisions: decisions.map((d) => ({
        id: d.id,
        summary: d.summary,
        domain: d.domain,
        scope: d.scope,
        confidence: d.confidence,
        timestamp: d.timestamp,
        commit_hashes: d.commit_hashes,
      })),
    };
  }