diff --git a/packages/hermes-tlon-adapter/adapter.py b/packages/hermes-tlon-adapter/adapter.py
index 0f18b289de..21340a00e9 100644
--- a/packages/hermes-tlon-adapter/adapter.py
+++ b/packages/hermes-tlon-adapter/adapter.py
@@ -4993,7 +4993,10 @@ def register(ctx) -> None:
             "and /tlon (version, status storage, status telemetry, status "
             "binary — debug info). Point the owner at those commands when asked "
             "rather than changing configuration yourself. "
-            "Use concise plain text and basic markdown."
+            "Use concise plain text and basic markdown. Never use LaTeX math "
+            "delimiters ($...$, $$...$$, \\(...\\), \\[...\\]) in note bodies "
+            "or message text — Tlon renders no math; write math as plain "
+            "text/Unicode or in code blocks."
             + _reaction_platform_hint(TlonConfig.from_env().reaction_level)
         ),
     )
diff --git a/packages/hermes-tlon-adapter/test_tlon_tool.py b/packages/hermes-tlon-adapter/test_tlon_tool.py
index e7c0235226..a73c789e77 100644
--- a/packages/hermes-tlon-adapter/test_tlon_tool.py
+++ b/packages/hermes-tlon-adapter/test_tlon_tool.py
@@ -345,6 +345,43 @@ def register_platform(self, **kwargs):
         self.assertIn("--parent <post-id>", platform_hint)
         self.assertIn("posts delete heap/~host/name <post-id>", platform_hint)
 
+    def test_tool_description_includes_latex_guidance(self):
+        description = tlon_tool.TLON_TOOL_DESCRIPTION
+
+        self.assertIn("Never use LaTeX math delimiters", description)
+        self.assertIn("$$...$$", description)
+        self.assertIn("\\(...\\)", description)
+        self.assertIn("\\[...\\]", description)
+        self.assertIn("plain text/Unicode", description)
+        self.assertIn("code blocks", description)
+
+        class RecordingContext:
+            def __init__(self):
+                self.platform = None
+
+            def register_hook(self, *_args):
+                pass
+
+            def register_tool(self, **_kwargs):
+                pass
+
+            def register_skill(self, *_args, **_kwargs):
+                pass
+
+            def register_platform(self, **kwargs):
+                self.platform = kwargs
+
+        context = RecordingContext()
+        adapter_mod.register(context)
+        platform_hint = context.platform["platform_hint"]
+
+        self.assertIn("Never use LaTeX math delimiters", platform_hint)
+        self.assertIn("$$...$$", platform_hint)
+        self.assertIn("\\(...\\)", platform_hint)
+        self.assertIn("\\[...\\]", platform_hint)
+        self.assertIn("plain text/Unicode", platform_hint)
+        self.assertIn("code blocks", platform_hint)
+
     def test_blocks_notebook(self):
         args, error = tlon_tool.split_tlon_command('notebook diary/~zod/notes "Title"')
         self.assertIsNone(error)
diff --git a/packages/hermes-tlon-adapter/tlon_tool.py b/packages/hermes-tlon-adapter/tlon_tool.py
index d12bd2f5e1..0dfaae1fa8 100644
--- a/packages/hermes-tlon-adapter/tlon_tool.py
+++ b/packages/hermes-tlon-adapter/tlon_tool.py
@@ -92,6 +92,9 @@ class _DiaryMigrationNotificationRegistration:
     "notes/~host/name nests). For notes bodies, use --body <file> "
     "(note-create also accepts --markdown <file>); --stdin is blocked because "
     "Hermes cannot pipe stdin into the CLI process. "
+    "Never use LaTeX math delimiters ($...$, $$...$$, \\(...\\), \\[...\\]) — "
+    "Tlon renders no math; write math as plain text/Unicode or in code "
+    "blocks. "
     "%diary channels are deprecated and unsupported by this tool. Ask the "
     "owner to type `/migrate <diary-nest>` to move one to %notes. Hermes "
     "delivery uses `tlon posts send`, which refuses diary/ targets. "
diff --git a/packages/openclaw/index.ts b/packages/openclaw/index.ts
index e995e55d1b..0ac4f3942a 100644
--- a/packages/openclaw/index.ts
+++ b/packages/openclaw/index.ts
@@ -972,6 +972,7 @@ export default defineBundledChannelEntry({
         'DO NOT use this tool to send messages — use the `message` tool instead. ' +
         '%diary channels are deprecated and unsupported by this CLI tool; ask the owner to type `/migrate <diary-nest>` to move one to %notes. ' +
         'OpenClaw message delivery still accepts diary/ targets, including writable archives. ' +
+        'Never use LaTeX math delimiters ($...$, $$...$$, \\(...\\), \\[...\\]) in note bodies or message text — Tlon renders no math; write math as plain text/Unicode or in code blocks. ' +
         "Examples: 'activity mentions --limit 10', 'channels groups', 'contacts self', 'groups list', 'notes list'",
       parameters: {
         type: 'object',
diff --git a/packages/tlon-skill/SKILL.md b/packages/tlon-skill/SKILL.md
index 52f41b10ff..007b9dfa4f 100644
--- a/packages/tlon-skill/SKILL.md
+++ b/packages/tlon-skill/SKILL.md
@@ -476,13 +476,21 @@ explanatory error). Deprecated diary channels are unmanaged by the CLI except
 through the owner-run `tlon notes migrate-plan <diary-nest>` and
 `tlon notes migrate-apply <diary-nest> --yes` paths.
 
-Message text supports Markdown lists, task lists, blockquotes, code, links, and ship mentions; raw HTML blocks and reference-style links are not supported.
+Message text supports Markdown lists, task lists, blockquotes, code, links, and ship mentions; raw HTML blocks and reference-style links are not supported. Never use LaTeX math delimiters ($...$, $$...$$, \(...\), \[...\]) — Tlon renders no math; write math as plain text/Unicode or in code blocks.
 
 ### Notes
 
 Manage %notes notebooks (Markdown-first). Notebooks are nests of the form
 `notes/~host/name`; note bodies are plain Markdown (not Tlon Story).
 
+Do not use LaTeX math delimiters (`$...$`, `$$...$$`, `\(...\)`, `\[...\]`) in
+note bodies or message text. No Tlon surface renders math: the delimiters
+display literally or get mangled (Markdown emphasis, mentions, and escaping can
+corrupt the text inside and around them), and in a note body the backslashes in
+`\(` and `\[` are silently eaten by Markdown escaping, so those delimiters
+vanish. Write math as plain text/Unicode (`x²`, `E = mc²`, `θ ∈ [0, 2π)`) and
+use code blocks or inline code for complex formulas.
+
 ```bash
 tlon notes status                                        # Check %notes reachability
 tlon notes request 0vabc                                 # Check a pending write request
diff --git a/packages/tlon-skill/scripts/commands/notes.ts b/packages/tlon-skill/scripts/commands/notes.ts
index 78c9d04e79..b02b00dac8 100644
--- a/packages/tlon-skill/scripts/commands/notes.ts
+++ b/packages/tlon-skill/scripts/commands/notes.ts
@@ -69,6 +69,9 @@ Content sources (Markdown):
   --markdown <file>   Alias for --body
   --stdin             Read the note body from stdin
 
+Note bodies are plain Markdown. LaTeX math delimiters ($...$, $$...$$,
+\\(...\\), \\[...\\]) do not render; use plain text/Unicode or code blocks.
+
 Examples:
   tlon notes list
   tlon notes request 0vabc