diff --git a/agent/coding_context.py b/agent/coding_context.py
index 723279abe..c5db3bdda 100644
--- a/agent/coding_context.py
+++ b/agent/coding_context.py
@@ -318,12 +318,11 @@ def _edit_format_line(model: Optional[str]) -> str:
     "Operate like a careful senior engineer.\n"
     "\n"
     "Gather context first:\n"
-    "- Before exploring an unfamiliar codebase, call `repo_map` FIRST — when it "
-    "is in your toolset and the codebase is Python (it is Python-only) — to get "
+    "- Before exploring an unfamiliar Python codebase, call `repo_map` FIRST to get "
     "a structured overview (functions/classes/methods with file:line and "
     "hot-symbol ranking). It is far cheaper than 10+ sequential "
     "`read_file`/`search_files` calls. After the overview, read only the "
-    "specific files you need. Without `repo_map`, start from `search_files`.\n"
+    "specific files you need.\n"
     "- Read the relevant files with `read_file` and locate code with "
     "`search_files` before changing anything. Trace a symbol to its definition "
     "and usages rather than guessing its shape.\n"
diff --git a/tests/agent/test_coding_context.py b/tests/agent/test_coding_context.py
index c74617b2c..ed123333c 100644
--- a/tests/agent/test_coding_context.py
+++ b/tests/agent/test_coding_context.py
@@ -14,7 +14,7 @@
 def test_coding_guidance_advertises_repo_map_first():
     assert "repo_map" in cc.CODING_AGENT_GUIDANCE
     assert (
-        "Before exploring an unfamiliar codebase, call `repo_map` FIRST"
+        "Before exploring an unfamiliar Python codebase, call `repo_map` FIRST"
         in cc.CODING_AGENT_GUIDANCE
     )
 
@@ -156,6 +156,7 @@ def test_coding_toolset_is_registered(self):
             "write_file",
             "patch",
             "search_files",
+            "repo_map",
             "terminal",
             "todo",
         ):
@@ -452,7 +453,9 @@ def test_coding_instructions_accept_a_list(self, tmp_path):
 
     def test_no_instructions_block_when_unset(self, tmp_path):
         _git_init(tmp_path)
-        mode = cc.resolve_runtime_mode(platform="cli", cwd=tmp_path, config={"agent": {"coding_context": "on"}})
+        mode = cc.resolve_runtime_mode(
+            platform="cli", cwd=tmp_path, config={"agent": {"coding_context": "on"}}
+        )
         assert not any("Operator instructions" in b for b in mode.system_blocks())
 
     def test_toolset_selection_gated_on_focus(self, tmp_path):
diff --git a/tests/test_toolsets.py b/tests/test_toolsets.py
index 1773d281a..0c4d203d2 100644
--- a/tests/test_toolsets.py
+++ b/tests/test_toolsets.py
@@ -61,6 +61,13 @@ def test_composite_toolset(self):
         assert "web_search" in tools
         assert "web_extract" in tools
 
+    def test_coding_posture_toolsets_expose_repo_map(self):
+        # The coding-posture brief and loop-guard nudges advise calling
+        # repo_map first; the toolsets they target must actually expose it
+        # (#669 — no prompt may advertise an uncallable tool).
+        assert "repo_map" in resolve_toolset("coding")
+        assert "repo_map" in resolve_toolset("hermes-acp")
+
     def test_cycle_detection(self):
         # Create a cycle: A includes B, B includes A
         TOOLSETS["_cycle_a"] = {"description": "test", "tools": ["t1"], "includes": ["_cycle_b"]}
diff --git a/toolsets.py b/toolsets.py
index 9f5bdc620..0d15ff250 100644
--- a/toolsets.py
+++ b/toolsets.py
@@ -193,7 +193,12 @@
     
 
     "file": {
-        "description": "File manipulation tools: read, write, patch (with fuzzy matching), and search (content + files)",
+        "description": "File manipulation tools: read, write, patch (with fuzzy matching), search (content + files), and repo_map (Python codebase overview)",
+        # repo_map is deliberately NOT listed here: it self-registers into this
+        # toolset at import time (tools/repo_map.py, toolset="file"). Listing it
+        # statically breaks hermes_cli/tools_config.py's composite-subset
+        # inference — 'file' must stay a subset of the static hermes-* platform
+        # tool lists, which do not carry repo_map.
         "tools": ["read_file", "write_file", "patch", "search_files"],
         "includes": []
     },
@@ -365,7 +370,7 @@
         "tools": [
             "web_search", "web_extract",
             "terminal", "process", "read_terminal", "close_terminal",
-            "read_file", "write_file", "patch", "search_files",
+            "read_file", "write_file", "patch", "search_files", "repo_map",
             "vision_analyze",
             "skills_list", "skill_view", "skill_manage",
             "browser_navigate", "browser_snapshot", "browser_click",
@@ -397,7 +402,7 @@
         "tools": [
             "web_search", "web_extract",
             "terminal", "process",
-            "read_file", "write_file", "patch", "search_files",
+            "read_file", "write_file", "patch", "search_files", "repo_map",
             "vision_analyze",
             "skills_list", "skill_view", "skill_manage",
             "browser_navigate", "browser_snapshot", "browser_click",