Method formatTrail

src/mcp/tools.ts:3915–3943

* Build the "trail" for a symbol: its direct callees (what it calls) and * callers (what calls it), each with file:line — so codegraph_node doubles as * the structural Grep→Read→expand primitive: a spot PLUS where to go next. * Capped to stay cheap. Walk the graph by calling codegraph_node

(cg: CodeGraph, node: Node)

   * a signal (read that one hop) rather than a dead end.
   */
  private formatTrail(cg: CodeGraph, node: Node): string {
    const TRAIL_CAP = 12;
    const fmt = (e: { node: Node; edge: Edge }) => {
      const base = `${e.node.name} (${e.node.filePath}:${e.node.startLine})`;
      const synth = this.synthEdgeNote(e.edge);
      return synth ? `${base} [${synth.compact}]` : base;
    };
    const collect = (edges: Array<{ node: Node; edge: Edge }>): Array<{ node: Node; edge: Edge }> => {
      const seen = new Set<string>([node.id]);
      const out: Array<{ node: Node; edge: Edge }> = [];
      for (const e of edges) {
        if (seen.has(e.node.id)) continue;
        seen.add(e.node.id);
        out.push(e);
      }
      return out;
    };
    const callees = collect(cg.getCallees(node.id));
    const callers = collect(cg.getCallers(node.id));
    if (callees.length === 0 && callers.length === 0) return '';
    const lines: string[] = ['', '**Trail — codegraph_node any of these to follow it (no Read needed)**'];
    if (callees.length > 0) {
      lines.push(`**Calls →** ${callees.slice(0, TRAIL_CAP).map(fmt).join(', ')}${callees.length > TRAIL_CAP ? `, +${callees.length - TRAIL_CAP} more` : ''}`);
    }
    if (callers.length > 0) {
      lines.push(`**Called by ←** ${callers.slice(0, TRAIL_CAP).map(fmt).join(', ')}${callers.length > TRAIL_CAP ? `, +${callers.length - TRAIL_CAP} more` : ''}`);
    }
    return lines.join('\n');
  }

  /**
   * Handle codegraph_status