Make max_tags_per_file configurable in auto-tag step

reme/config/default.yaml

@@ -189,6 +189,7 @@ jobs:
     steps:
       - backend: auto_memory_step
       - backend: auto_tag_step
+        max_tags_per_file: 3
 
   auto_memory_cc:
     backend: base

reme/steps/evolve/auto_tag.py

@@ -13,8 +13,8 @@ from ..file_io._path import display_path, resolve_path
 from ..index import normalize_posix_path
 from ...components import R
 
-_MAX_MEMORY_TAGS = 3
-_MAX_MEMORY_TAG_LENGTH = 64
+_DEFAULT_MAX_MEMORY_TAGS = 3
+_DEFAULT_MAX_MEMORY_TAG_LENGTH = 64
 _SUPPORTED_CHANGES = {"added", "modified"}
 
 
@@ -24,8 +24,21 @@ class _TagTarget:
     path: str
 
 
-def normalize_memory_tags(value: object) -> list[str]:
-    """Normalize up to three human-readable entity labels for frontmatter storage."""
+def _positive_int(value: object, *, name: str) -> int:
+    if isinstance(value, bool) or not isinstance(value, int) or value <= 0:
+        raise ValueError(f"{name} must be a positive integer")
+    return value
+
+
+def normalize_memory_tags(
+    value: object,
+    *,
+    max_tags_per_file: int = _DEFAULT_MAX_MEMORY_TAGS,
+    max_tag_length: int = _DEFAULT_MAX_MEMORY_TAG_LENGTH,
+) -> list[str]:
+    """Normalize human-readable entity labels for frontmatter storage."""
+    max_tags_per_file = _positive_int(max_tags_per_file, name="max_tags_per_file")
+    max_tag_length = _positive_int(max_tag_length, name="max_tag_length")
     if not isinstance(value, list):
         return []
 
@@ -35,14 +48,14 @@ def normalize_memory_tags(value: object) -> list[str]:
         if not isinstance(item, str):
             continue
         tag = " ".join(item.split())
-        if not tag or len(tag) > _MAX_MEMORY_TAG_LENGTH or not any(char.isalnum() for char in tag):
+        if not tag or len(tag) > max_tag_length or not any(char.isalnum() for char in tag):
             continue
         canonical = tag.casefold()
         if canonical in seen:
             continue
         seen.add(canonical)
         tags.append(tag)
-        if len(tags) >= _MAX_MEMORY_TAGS:
+        if len(tags) >= max_tags_per_file:
             break
     return tags
 
@@ -51,10 +64,22 @@ def normalize_memory_tags(value: object) -> list[str]:
 class AutoTagStep(BaseStep):
     """Update memory tags for Markdown files described by the common ``changes`` contract."""
 
-    def __init__(self, **kwargs):
+    def __init__(self, max_tags_per_file: int = _DEFAULT_MAX_MEMORY_TAGS, **kwargs):
         super().__init__(**kwargs)
+        self.max_tags_per_file = _positive_int(max_tags_per_file, name="max_tags_per_file")
         self.tools = ["read", "list_tags", "frontmatter_read", "frontmatter_update"]
 
+    @staticmethod
+    def _index_limit(tag_index, name: str, fallback: int | None) -> int | None:
+        """Read one positive integer index limit, falling back when unavailable or invalid."""
+        try:
+            value = getattr(tag_index, name)
+        except (AttributeError, TypeError, ValueError):
+            return fallback
+        if isinstance(value, bool) or not isinstance(value, int) or value <= 0:
+            return fallback
+        return value
+
     def _targets(self) -> tuple[list[_TagTarget], list[dict[str, str]]]:
         """Validate, normalize, and de-duplicate added/modified Markdown changes."""
         assert self.context is not None
@@ -94,10 +119,14 @@ class AutoTagStep(BaseStep):
             targets[path] = _TagTarget(change=normalized_change, path=path)
         return list(targets.values()), ignored
 
-    async def _process_target(self, target: _TagTarget, tag_key: str) -> str:
+    async def _process_target(self, target: _TagTarget, tag_key: str, max_tag_length: int) -> str:
         result = await self.agent_wrapper.reply(
             self.prompt_format("user_message", path=target.path, change=target.change, tag_key=tag_key),
-            system_prompt=self.prompt_format("system_prompt", tag_key=tag_key),
+            system_prompt=self.prompt_format(
+                "system_prompt",
+                tag_key=tag_key,
+                max_tags_per_file=self.max_tags_per_file,
+            ),
             job_tools=self.tools,
             injected_job_kwargs={
                 "_allowed_paths": [target.path],
@@ -107,7 +136,11 @@ class AutoTagStep(BaseStep):
 
         path = Path(self.file_store.workspace_path or ".") / target.path
         metadata = dict(frontmatter.loads(path.read_text(encoding="utf-8")).metadata or {})
-        normalized = normalize_memory_tags(metadata.get(tag_key))
+        normalized = normalize_memory_tags(
+            metadata.get(tag_key),
+            max_tags_per_file=self.max_tags_per_file,
+            max_tag_length=max_tag_length,
+        )
         if metadata.get(tag_key) != normalized:
             response = await self.run_job(
                 "frontmatter_update",
@@ -148,12 +181,23 @@ class AutoTagStep(BaseStep):
             return self.context.response
 
         tag_index = self.file_store.require_tag_index() if targets else None
+        max_tag_length = self._index_limit(tag_index, "max_tag_length", _DEFAULT_MAX_MEMORY_TAG_LENGTH)
+        index_max_tags = self._index_limit(tag_index, "max_tags_per_file", None)
+        if index_max_tags is not None and self.max_tags_per_file > index_max_tags:
+            self.context.response.success = False
+            if initial_success:
+                self.context.response.answer = (
+                    f"Error: auto_tag max_tags_per_file ({self.max_tags_per_file}) exceeds "
+                    f"tag index limit ({index_max_tags})"
+                )
+            return self.context.response
+
         dates: set[str] = set()
         for target in targets:
             if day := self._daily_date(target.path):
                 dates.add(day)
             try:
-                summary = await self._process_target(target, tag_index.tag_key)
+                summary = await self._process_target(target, tag_index.tag_key, max_tag_length)
                 results.append(
                     {"change": target.change, "path": target.path, "success": True, "summary": summary},
                 )

reme/steps/evolve/auto_tag.yaml

@@ -6,9 +6,9 @@ system_prompt: |
   Required workflow:
   1. Use `read` and `frontmatter_read` to inspect the complete target document and its current frontmatter.
   2. Use `list_tags` to inspect tags already used in the workspace. Check additional pages when useful.
-  3. Prefer one primary entity that best answers the question. Use two or three tags only when the memory is genuinely
-     about multiple independent central entities, and never use more than three. Prefer an existing tag whenever it
-     represents the same entity. Tags must not contain spaces; replace spaces with underscores, for example
+  3. Prefer one primary entity that best answers the question. Use multiple tags only when the memory is genuinely
+     about multiple independent central entities, and never use more than {max_tags_per_file}. Prefer an existing tag
+     whenever it represents the same entity. Tags must not contain spaces; replace spaces with underscores, for example
      `sam_altman`. Examples include a person (`sam_altman`), an organization (`OpenAI`), or an asset/entity (`gold`).
   4. Use `frontmatter_update` to write the complete `{tag_key}` list, including `[]` when no entity is central.
 
@@ -25,9 +25,9 @@ system_prompt_zh: |
   1. 使用 `read` 和 `frontmatter_read` 阅读目标文档的完整内容及当前 frontmatter。
   2. 使用 `list_tags` 查看工作区已经使用的标签；必要时继续查看后续分页。
   3. 默认只选择一个最能回答上述问题的主实体。只有当记忆确实同时围绕多个相互独立的核心实体时，才选择
-     两个或三个标签，并且绝不能超过三个。同一实体已有标签时必须优先复用。标签中不能包含空格；如有空格，
-     必须替换为下划线，例如将 `Sam Altman` 写成 `sam_altman`。实体可以是人物（如 `sam_altman`）、组织或
-     公司（如 `宁德时代`），也可以是资产等实体（如 `黄金`）。
+     多个标签，并且绝不能超过 {max_tags_per_file} 个。同一实体已有标签时必须优先复用。标签中不能包含空格；
+     如有空格，必须替换为下划线，例如将 `Sam Altman` 写成 `sam_altman`。实体可以是人物（如 `sam_altman`）、
+     组织或公司（如 `宁德时代`），也可以是资产等实体（如 `黄金`）。
   4. 使用 `frontmatter_update` 写入完整的 `{tag_key}` 列表；没有核心实体时也要写入 `[]`。
 
   只选择实体，不要使用宽泛主题、行为、属性、日期或普通关键词。每个实体使用一个简洁、规范的现实名称。

tests/unit/test_auto_tag.py

@@ -180,13 +180,13 @@ async def test_auto_tag_uses_configured_key_and_normalizes_agent_output(tmp_path
     note = tmp_path / "memory/note.md"
     _write_note(note)
     store = LocalFileStore(name="store", embedding_store="", tag_index="")
-    store.tag_index = LocalTagIndex(tag_key="keywords")
+    store.tag_index = LocalTagIndex(tag_key="keywords", max_tag_length=8)
     wrapper = _TaggingWrapper(
         tmp_path,
         tag_key="keywords",
         tags=["OpenAI", "openai", "Sam   Altman", "++", 100, "宁德时代", "黄金"],
     )
-    step = AutoTagStep(file_store=store, agent_wrapper=wrapper)
+    step = AutoTagStep(file_store=store, agent_wrapper=wrapper, max_tags_per_file=2)
 
     async def update_frontmatter(name, /, **kwargs):
         assert name == "frontmatter_update"
@@ -206,7 +206,6 @@ async def test_auto_tag_uses_configured_key_and_normalizes_agent_output(tmp_path
     assert response.answer == "Created memory/note.md"
     assert frontmatter.loads(note.read_text(encoding="utf-8")).metadata["keywords"] == [
         "OpenAI",
-        "Sam Altman",
         "宁德时代",
     ]
     assert "Change: modified" in wrapper.calls[0][0]
@@ -225,3 +224,27 @@ def test_normalize_memory_tags_enforces_entity_storage_contract():
             "黄金",
         ],
     ) == ["OpenAI", "Sam Altman", "宁德时代"]
+    assert normalize_memory_tags(
+        ["one", "two", "three"],
+        max_tags_per_file=2,
+        max_tag_length=3,
+    ) == ["one", "two"]
+
+
+@pytest.mark.asyncio
+async def test_auto_tag_rejects_limit_above_tag_index_ceiling(tmp_path, monkeypatch):
+    monkeypatch.chdir(tmp_path)
+    note = tmp_path / "memory/note.md"
+    _write_note(note)
+    before = note.read_bytes()
+    store = LocalFileStore(name="store", embedding_store="", tag_index="")
+    store.tag_index = LocalTagIndex(max_tags_per_file=2)
+    wrapper = _TaggingWrapper(tmp_path)
+    step = AutoTagStep(file_store=store, agent_wrapper=wrapper, max_tags_per_file=3)
+
+    response = await step(RuntimeContext(changes=[{"change": "modified", "path": "memory/note.md"}]))
+
+    assert response.success is False
+    assert response.answer == "Error: auto_tag max_tags_per_file (3) exceeds tag index limit (2)"
+    assert not wrapper.calls
+    assert note.read_bytes() == before

tests/unit/test_injected_job_kwargs.py

@@ -282,7 +282,7 @@ def test_configs_define_original_jobs_without_daily_variants():
     default = resolve_app_config(config="default", log_config=False)
     assert default["jobs"]["auto_memory"]["steps"] == [
         {"backend": "auto_memory_step"},
-        {"backend": "auto_tag_step"},
+        {"backend": "auto_tag_step", "max_tags_per_file": 3},
     ]
 
 

tests/unit/test_tag_index.py

@@ -570,5 +570,5 @@ def test_default_config_enables_tag_index_with_explicit_key() -> None:
     assert config["jobs"]["search"]["parameters"]["properties"]["tags"]["default"] == []
     assert config["jobs"]["auto_memory"]["steps"] == [
         {"backend": "auto_memory_step"},
-        {"backend": "auto_tag_step"},
+        {"backend": "auto_tag_step", "max_tags_per_file": 3},
     ]