Claude Code 输出格式控制完全指南：JSON、流式、结构化输出使用方法

# 最简单，直接输出 Claude 的文字回复
claude -p "列出 Python 列表去重的 3 种方法"

# 输出：
# 1. 使用 set()：list(set(lst))
# 2. 使用 dict.fromkeys()：list(dict.fromkeys(lst))
# 3. 使用列表推导：[x for i, x in enumerate(lst) if x not in lst[:i]]

claude -p "分析这段代码有什么问题" --output-format json

{
  "type": "result",
  "subtype": "success",
  "session_id": "session_abc123",
  "cost_usd": 0.00234,
  "duration_ms": 2341,
  "num_turns": 1,
  "result": "分析结果：该代码存在以下问题...",
  "is_error": false
}

# 提取 result 字段
RESULT=$(claude -p "分析代码" --output-format json | python3 -c "
import json, sys
data = json.load(sys.stdin)
print(data['result'])
")
echo "$RESULT"

import subprocess, json

output = subprocess.run(
    ["claude", "-p", "分析这段代码", "--output-format", "json"],
    capture_output=True, text=True
)
data = json.loads(output.stdout)
print(data["result"])
print(f"耗时：{data['duration_ms']}ms，成本：${data['cost_usd']:.4f}")

claude -p "写一篇 2000 字的技术文章"   --output-format stream-json   --include-partial-messages

{"type": "system", "subtype": "init", "session_id": "xxx", ...}
{"type": "assistant", "message": {"role": "assistant", "content": [{"type": "text", "text": "# 文章标题

第一段..."}]}, "turn_number": 1}
{"type": "result", "subtype": "success", "cost_usd": 0.05, ...}

import subprocess, json

process = subprocess.Popen(
    ["claude", "-p", "写一篇长文", "--output-format", "stream-json",
     "--include-partial-messages"],
    stdout=subprocess.PIPE, text=True
)

for line in process.stdout:
    line = line.strip()
    if not line:
        continue
    event = json.loads(line)
    if event["type"] == "assistant":
        # 实时打印流式内容
        for block in event["message"]["content"]:
            if block["type"] == "text":
                print(block["text"], end="", flush=True)
    elif event["type"] == "result":
        print(f"

成本：${event['cost_usd']:.4f}")

claude -p "分析这段 Python 代码的问题"   --output-format json   --json-schema '{
    "type": "object",
    "properties": {
      "issues": {
        "type": "array",
        "items": {
          "type": "object",
          "properties": {
            "severity": {"type": "string", "enum": ["critical", "major", "minor"]},
            "line": {"type": "integer"},
            "description": {"type": "string"},
            "suggestion": {"type": "string"}
          }
        }
      },
      "overall_score": {"type": "integer", "minimum": 0, "maximum": 100}
    }
  }'

{
  "issues": [
    {
      "severity": "major",
      "line": 15,
      "description": "未处理异常可能导致程序崩溃",
      "suggestion": "添加 try-except 块"
    }
  ],
  "overall_score": 72
}

# .github/workflows/code-review.yml
- name: AI Code Review
  run: |
    REVIEW=$(claude -p "对以下改动做代码审查，输出 JSON"       --output-format json       --json-schema '{"type":"object","properties":{"approved":{"type":"boolean"},"issues":{"type":"array","items":{"type":"string"}}}}'       < git_diff.txt)

    APPROVED=$(echo "$REVIEW" | python3 -c "import json,sys; print(json.load(sys.stdin)['result'])" | python3 -c "import json,sys; d=json.load(sys.stdin); print(d.get('approved','false'))")

    if [ "$APPROVED" = "false" ]; then
      echo "AI 审查未通过"
      exit 1
    fi

# 接收流式 JSON 输入，输出 JSON
some-tool --output stream-json |   claude -p "总结以上内容"     --input-format stream-json     --output-format json