Add RFC 9457 problem+json parsing

README.md

@@ -13,6 +13,7 @@
 
 ## Table of Contents
 
+- [What's new (2026-06-21) — RFC 9457 Problem Details Parsing](#whats-new-2026-06-21--rfc-9457-problem-details-parsing)
 - [What's new (2026-06-21) — Data Profiling & Schema Inference](#whats-new-2026-06-21--data-profiling--schema-inference)
 - [What's new (2026-06-21) — W3C Trace Context Propagation](#whats-new-2026-06-21--w3c-trace-context-propagation)
 - [What's new (2026-06-21) — HTTP Record & Replay Cassette](#whats-new-2026-06-21--http-record--replay-cassette)
@@ -130,6 +131,12 @@
 
 ---
 
+## What's new (2026-06-21) — RFC 9457 Problem Details Parsing
+
+Read standardized API errors out of HTTP responses. Full reference: [`docs/source/Eng/doc/new_features/v78_features_doc.rst`](docs/source/Eng/doc/new_features/v78_features_doc.rst).
+
+- **`parse_problem` / `is_problem` / `raise_for_problem` / `ProblemDetails`** (`AC_parse_problem`): `http_request` returned a non-2xx body unparsed, so flows and `assert_http` had no structured way to read a standardized API error. This parses the RFC 9457 `application/problem+json` document — registered `type`/`title`/`status`/`detail`/`instance` members plus vendor extensions — returning `None` for non-problem responses or raising `HttpProblemError`. Pure-stdlib, fully deterministic.
+
 ## What's new (2026-06-21) — Data Profiling & Schema Inference
 
 Survey a row-set and propose a validation schema. Full reference: [`docs/source/Eng/doc/new_features/v77_features_doc.rst`](docs/source/Eng/doc/new_features/v77_features_doc.rst).

README/README_zh-CN.md

@@ -12,6 +12,7 @@
 
 ## 目录
 
+- [本次更新 (2026-06-21) — RFC 9457 Problem Details 解析](#本次更新-2026-06-21--rfc-9457-problem-details-解析)
 - [本次更新 (2026-06-21) — 数据剖析与结构推断](#本次更新-2026-06-21--数据剖析与结构推断)
 - [本次更新 (2026-06-21) — W3C Trace Context 传播](#本次更新-2026-06-21--w3c-trace-context-传播)
 - [本次更新 (2026-06-21) — HTTP 录制与重播卡带](#本次更新-2026-06-21--http-录制与重播卡带)
@@ -129,6 +130,12 @@
 
 ---
 
+## 本次更新 (2026-06-21) — RFC 9457 Problem Details 解析
+
+从 HTTP 响应读取标准化的 API 错误。完整参考:[`docs/source/Zh/doc/new_features/v78_features_doc.rst`](../docs/source/Zh/doc/new_features/v78_features_doc.rst)。
+
+- **`parse_problem` / `is_problem` / `raise_for_problem` / `ProblemDetails`**(`AC_parse_problem`):`http_request` 返回的非 2xx 内文未经解析,因此流程与 `assert_http` 无法以结构化方式读取标准化的 API 错误。本功能解析 RFC 9457 `application/problem+json` 文档 —— 已注册的 `type`/`title`/`status`/`detail`/`instance` 成员加上 vendor 扩展字段 —— 对非 problem 响应返回 `None`,或抛出 `HttpProblemError`。纯标准库、完全确定。
+
 ## 本次更新 (2026-06-21) — 数据剖析与结构推断
 
 扫描数据行集合并提出验证结构。完整参考:[`docs/source/Zh/doc/new_features/v77_features_doc.rst`](../docs/source/Zh/doc/new_features/v77_features_doc.rst)。

README/README_zh-TW.md

@@ -12,6 +12,7 @@
 
 ## 目錄
 
+- [本次更新 (2026-06-21) — RFC 9457 Problem Details 解析](#本次更新-2026-06-21--rfc-9457-problem-details-解析)
 - [本次更新 (2026-06-21) — 資料剖析與結構推斷](#本次更新-2026-06-21--資料剖析與結構推斷)
 - [本次更新 (2026-06-21) — W3C Trace Context 傳播](#本次更新-2026-06-21--w3c-trace-context-傳播)
 - [本次更新 (2026-06-21) — HTTP 錄製與重播卡帶](#本次更新-2026-06-21--http-錄製與重播卡帶)
@@ -129,6 +130,12 @@
 
 ---
 
+## 本次更新 (2026-06-21) — RFC 9457 Problem Details 解析
+
+從 HTTP 回應讀取標準化的 API 錯誤。完整參考:[`docs/source/Zh/doc/new_features/v78_features_doc.rst`](../docs/source/Zh/doc/new_features/v78_features_doc.rst)。
+
+- **`parse_problem` / `is_problem` / `raise_for_problem` / `ProblemDetails`**(`AC_parse_problem`):`http_request` 回傳的非 2xx 內文未經解析,因此流程與 `assert_http` 無法以結構化方式讀取標準化的 API 錯誤。本功能解析 RFC 9457 `application/problem+json` 文件 —— 已註冊的 `type`/`title`/`status`/`detail`/`instance` 成員加上 vendor 擴充欄位 —— 對非 problem 回應回傳 `None`,或拋出 `HttpProblemError`。純標準函式庫、完全具決定性。
+
 ## 本次更新 (2026-06-21) — 資料剖析與結構推斷
 
 掃描資料列集合並提出驗證結構。完整參考:[`docs/source/Zh/doc/new_features/v77_features_doc.rst`](../docs/source/Zh/doc/new_features/v77_features_doc.rst)。

docs/source/Eng/doc/new_features/v78_features_doc.rst

@@ -0,0 +1,44 @@
+RFC 9457 Problem Details Parsing
+================================
+
+``http_request`` returns a non-2xx body unparsed, so a flow — or
+``assert_http`` — had no structured way to read a standardised API error.
+This parses the RFC 9457 ``application/problem+json`` document: the registered
+``type`` / ``title`` / ``status`` / ``detail`` / ``instance`` members plus any
+vendor extensions.
+
+Pure standard library (``json``); imports no ``PySide6``. Every function is
+pure (response dict in, dataclass out), so it is fully deterministic in CI.
+
+Headless API
+------------
+
+.. code-block:: python
+
+    from je_auto_control import http_request, parse_problem, raise_for_problem
+
+    response = http_request("https://api.example.com/orders/12")
+    problem = parse_problem(response)        # None unless problem+json
+    if problem is not None:
+        log(problem.status, problem.title, problem.detail)
+        retry_after = problem.extensions.get("balance")
+
+    # or convert a problem response into an exception:
+    raise_for_problem(response)              # raises HttpProblemError
+
+``is_problem`` checks the ``Content-Type`` (case-insensitively).
+``parse_problem`` returns a ``ProblemDetails`` (``type`` defaulting to
+``about:blank``, an integer ``status`` when coercible, and all non-registered
+keys collected into ``extensions``) or ``None`` when the response is not a
+problem document; it falls back to parsing ``text`` when ``json`` is absent.
+``ProblemDetails.summary`` gives a one-line description and ``to_dict`` flattens
+the document with extensions merged back in. ``raise_for_problem`` raises
+``HttpProblemError`` (carrying the ``ProblemDetails``) for a problem response
+and does nothing otherwise.
+
+Executor command
+----------------
+
+``AC_parse_problem`` takes an ``http_request`` ``response`` and returns
+``{problem}`` (the flattened document) or ``null``. It is exposed as the MCP
+tool ``ac_parse_problem`` and as a Script Builder command under **Data**.

docs/source/Eng/eng_index.rst

@@ -100,6 +100,7 @@ Comprehensive guides for all AutoControl features.
    doc/new_features/v75_features_doc
    doc/new_features/v76_features_doc
    doc/new_features/v77_features_doc
+   doc/new_features/v78_features_doc
    doc/ocr_backends/ocr_backends_doc
    doc/observability/observability_doc
    doc/operations_layer/operations_layer_doc

docs/source/Zh/doc/new_features/v78_features_doc.rst

@@ -0,0 +1,37 @@
+RFC 9457 Problem Details 解析
+============================
+
+``http_request`` 回傳的非 2xx 內文未經解析,因此流程 —— 或 ``assert_http`` —— 無法以結構化方式讀取
+標準化的 API 錯誤。本功能解析 RFC 9457 ``application/problem+json`` 文件:已註冊的 ``type`` /
+``title`` / ``status`` / ``detail`` / ``instance`` 成員,加上任何 vendor 擴充欄位。
+
+純標準函式庫(``json``);不匯入 ``PySide6``。每個函式皆為純函式(輸入 response dict、輸出 dataclass),
+因此在 CI 中完全具決定性。
+
+無頭 API
+--------
+
+.. code-block:: python
+
+    from je_auto_control import http_request, parse_problem, raise_for_problem
+
+    response = http_request("https://api.example.com/orders/12")
+    problem = parse_problem(response)        # 非 problem+json 時為 None
+    if problem is not None:
+        log(problem.status, problem.title, problem.detail)
+        retry_after = problem.extensions.get("balance")
+
+    # 或把 problem 回應轉成例外:
+    raise_for_problem(response)              # 拋出 HttpProblemError
+
+``is_problem`` 檢查 ``Content-Type``(不分大小寫)。``parse_problem`` 回傳 ``ProblemDetails``
+(``type`` 預設 ``about:blank``,可轉換時 ``status`` 為整數,所有非註冊鍵收進 ``extensions``),
+回應非 problem 文件時回傳 ``None``;當 ``json`` 缺席時會回退去解析 ``text``。``ProblemDetails.summary``
+給出一行描述,``to_dict`` 把文件攤平並併回擴充欄位。``raise_for_problem`` 對 problem 回應拋出
+``HttpProblemError``(帶著 ``ProblemDetails``),否則不做任何事。
+
+執行器命令
+----------
+
+``AC_parse_problem`` 接受 ``http_request`` 的 ``response``,回傳 ``{problem}``(攤平的文件)或
+``null``。它以 MCP 工具 ``ac_parse_problem`` 以及 Script Builder 中 **Data** 分類下的命令提供。

docs/source/Zh/zh_index.rst

@@ -100,6 +100,7 @@ AutoControl 所有功能的完整使用指南。
    doc/new_features/v75_features_doc
    doc/new_features/v76_features_doc
    doc/new_features/v77_features_doc
+   doc/new_features/v78_features_doc
    doc/ocr_backends/ocr_backends_doc
    doc/observability/observability_doc
    doc/operations_layer/operations_layer_doc

je_auto_control/__init__.py

@@ -379,6 +379,11 @@
 )
 # HTTP record/replay cassette (deterministic offline API tests)
 from je_auto_control.utils.http_cassette import Cassette, CassetteMissError
+# RFC 9457 problem+json error parsing
+from je_auto_control.utils.http_problem import (
+    HttpProblemError, ProblemDetails, is_problem, parse_problem,
+    raise_for_problem,
+)
 # W3C Trace Context propagation (traceparent / tracestate)
 from je_auto_control.utils.trace_context import (
     SpanContext, TraceContextError, child_context, extract_context,
@@ -886,6 +891,8 @@ def start_autocontrol_gui(*args, **kwargs):
     "Bulkhead", "BulkheadFullError", "next_delay", "parse_ratelimit",
     "parse_retry_after",
     "Cassette", "CassetteMissError",
+    "HttpProblemError", "ProblemDetails", "is_problem", "parse_problem",
+    "raise_for_problem",
     "SpanContext", "TraceContextError", "child_context", "extract_context",
     "format_traceparent", "format_tracestate", "inject_context",
     "new_root_context", "new_span_id", "new_trace_id", "parse_traceparent",

je_auto_control/gui/script_builder/command_schema.py

@@ -1644,6 +1644,16 @@ def _add_resilience_specs(specs: List[CommandSpec]) -> None:
         ),
         description="Infer a validate_rows-compatible schema from observed rows.",
     ))
+    specs.append(CommandSpec(
+        "AC_parse_problem", "Data", "HTTP Problem (RFC 9457): Parse",
+        fields=(
+            FieldSpec("response", FieldType.STRING,
+                      placeholder='{"status": 400, "headers": '
+                                  '{"Content-Type": "application/problem+json"}, '
+                                  '"json": {"title": "Bad Request"}}'),
+        ),
+        description="Parse an application/problem+json error response.",
+    ))
     specs.append(CommandSpec(
         "AC_rate_limit", "Flow", "Rate Limit (Token Bucket)",
         fields=(

je_auto_control/utils/executor/action_executor.py

@@ -3022,6 +3022,16 @@ def _infer_schema(rows: Any, columns: Any = None) -> Dict[str, Any]:
     return {"schema": infer_schema(rows, columns)}
 
 
+def _parse_problem(response: Any) -> Dict[str, Any]:
+    """Adapter: parse an RFC 9457 problem+json HTTP response."""
+    import json
+    from je_auto_control.utils.http_problem import parse_problem
+    if isinstance(response, str):
+        response = json.loads(response)
+    problem = parse_problem(response)
+    return {"problem": problem.to_dict() if problem is not None else None}
+
+
 def _percentiles(samples: Any, qs: Any = None) -> Dict[str, Any]:
     """Adapter: exact percentiles of a numeric sample list (or JSON string)."""
     import json
@@ -4102,6 +4112,7 @@ def __init__(self):
             "AC_trace_extract": _trace_extract,
             "AC_profile_rows": _profile_rows,
             "AC_infer_schema": _infer_schema,
+            "AC_parse_problem": _parse_problem,
             "AC_unified_diff": _unified_diff,
             "AC_apply_unified": _apply_unified,
             "AC_three_way_merge": _three_way_merge,

je_auto_control/utils/http_problem/__init__.py

@@ -0,0 +1,10 @@
+"""RFC 9457 problem+json parsing for AutoControl HTTP responses."""
+from je_auto_control.utils.http_problem.http_problem import (
+    HttpProblemError, ProblemDetails, is_problem, parse_problem,
+    raise_for_problem,
+)
+
+__all__ = [
+    "HttpProblemError", "ProblemDetails", "is_problem", "parse_problem",
+    "raise_for_problem",
+]

je_auto_control/utils/http_problem/http_problem.py

@@ -0,0 +1,106 @@
+"""Parse RFC 9457 ``application/problem+json`` error responses.
+
+``http_request`` returns a non-2xx body unparsed, so a flow (or ``assert_http``)
+had no structured way to read a standardised API error. This reads the RFC 9457
+problem document — the registered ``type`` / ``title`` / ``status`` / ``detail``
+/ ``instance`` members plus any vendor extensions.
+
+Pure standard library (``json``); imports no ``PySide6``. Every function is pure
+(response dict in, dataclass out) so it is fully deterministic in CI.
+"""
+import json
+from dataclasses import dataclass, field
+from typing import Any, Dict, Mapping, Optional
+
+from je_auto_control.utils.exception.exceptions import AutoControlException
+
+_PROBLEM_MEDIA_TYPE = "application/problem+json"
+_REGISTERED = ("type", "title", "status", "detail", "instance")
+
+
+class HttpProblemError(AutoControlException):
+    """Raised by :func:`raise_for_problem` when a response is a problem."""
+
+    def __init__(self, problem: "ProblemDetails") -> None:
+        super().__init__(problem.summary())
+        self.problem = problem
+
+
+@dataclass(frozen=True)
+class ProblemDetails:
+    """An RFC 9457 problem document."""
+
+    type: str = "about:blank"
+    title: Optional[str] = None
+    status: Optional[int] = None
+    detail: Optional[str] = None
+    instance: Optional[str] = None
+    extensions: Dict[str, Any] = field(default_factory=dict)
+
+    def summary(self) -> str:
+        """A short ``status title — detail`` description."""
+        head = " ".join(str(part) for part in (self.status, self.title) if part)
+        return f"{head} — {self.detail}" if self.detail else (head or self.type)
+
+    def to_dict(self) -> Dict[str, Any]:
+        """Return the document as a flat dict (extensions merged in)."""
+        out: Dict[str, Any] = {"type": self.type}
+        for name in ("title", "status", "detail", "instance"):
+            value = getattr(self, name)
+            if value is not None:
+                out[name] = value
+        out.update(self.extensions)
+        return out
+
+
+def is_problem(headers: Optional[Mapping[str, Any]]) -> bool:
+    """Whether ``headers`` advertise an ``application/problem+json`` body."""
+    for key, value in (headers or {}).items():
+        if str(key).lower() == "content-type":
+            return _PROBLEM_MEDIA_TYPE in str(value).lower()
+    return False
+
+
+def _coerce_status(value: Any) -> Optional[int]:
+    try:
+        return int(value) if value is not None else None
+    except (TypeError, ValueError):
+        return None
+
+
+def _from_document(document: Mapping[str, Any]) -> ProblemDetails:
+    extensions = {key: value for key, value in document.items()
+                  if key not in _REGISTERED}
+    return ProblemDetails(
+        type=str(document.get("type", "about:blank")),
+        title=document.get("title"),
+        status=_coerce_status(document.get("status")),
+        detail=document.get("detail"),
+        instance=document.get("instance"),
+        extensions=extensions)
+
+
+def parse_problem(response: Mapping[str, Any]) -> Optional[ProblemDetails]:
+    """Parse a problem document from an ``http_request`` response, or ``None``.
+
+    Returns ``None`` unless the response advertises ``application/problem+json``
+    and carries a JSON object body.
+    """
+    if not is_problem(response.get("headers")):
+        return None
+    document = response.get("json")
+    if document is None and response.get("text"):
+        try:
+            document = json.loads(response["text"])
+        except (ValueError, TypeError):
+            return None
+    if not isinstance(document, dict):
+        return None
+    return _from_document(document)
+
+
+def raise_for_problem(response: Mapping[str, Any]) -> None:
+    """Raise :class:`HttpProblemError` when ``response`` is a problem document."""
+    problem = parse_problem(response)
+    if problem is not None:
+        raise HttpProblemError(problem)

je_auto_control/utils/mcp_server/tools/_factories.py

@@ -3343,6 +3343,21 @@ def rate_limit_tools() -> List[MCPTool]:
     ]
 
 
+def http_problem_tools() -> List[MCPTool]:
+    return [
+        MCPTool(
+            name="ac_parse_problem",
+            description=("Parse an RFC 9457 application/problem+json HTTP "
+                         "'response' ({status, headers, json}). Returns "
+                         "{problem} (type/title/status/detail/instance + "
+                         "extensions) or null when not a problem document."),
+            input_schema=schema({"response": {"type": "object"}}, ["response"]),
+            handler=h.parse_problem,
+            annotations=READ_ONLY,
+        ),
+    ]
+
+
 def data_profile_tools() -> List[MCPTool]:
     return [
         MCPTool(
@@ -4932,7 +4947,7 @@ def media_assert_tools() -> List[MCPTool]:
     search_index_tools, stats_tools, recurrence_tools, text_diff_tools,
     feature_flag_tools, provenance_tools, json_contract_tools, chaos_tools,
     slo_tools, percentiles_tools, bulkhead_tools, http_cassette_tools,
-    trace_context_tools, data_profile_tools,
+    trace_context_tools, data_profile_tools, http_problem_tools,
     saga_tools, decision_table_tools, locator_repair_tools,
     pii_text_tools, sarif_tools,
     screen_record_tools,

je_auto_control/utils/mcp_server/tools/_handlers.py

@@ -1736,6 +1736,11 @@ def infer_schema(rows, columns=None):
     return _infer_schema(rows, columns)
 
 
+def parse_problem(response):
+    from je_auto_control.utils.executor.action_executor import _parse_problem
+    return _parse_problem(response)
+
+
 def build_provenance(paths, builder_id="je_auto_control"):
     from je_auto_control.utils.provenance import build_provenance, subject_for
     subjects = [subject_for(path) for path in paths]