diff --git a/docs/agents/behaviour-catalog.md b/docs/agents/behaviour-catalog.md
new file mode 100644
index 0000000000..be48d160b6
--- /dev/null
+++ b/docs/agents/behaviour-catalog.md
@@ -0,0 +1,164 @@
+# Behaviour catalog
+
+Generated from `agent_comms.behaviour_patterns` by
+`python -m agent_comms.behaviour_patterns > docs/agents/behaviour-catalog.md`; do not edit by hand.
+
+Each behaviour failure pattern is declared once in Core with its signature (what it looks like in state, readable without trusting a report) and the existing checks that enforce it. Patterns in code, rather than in behaviour, are the refactor-audit skill's catalog (`refactor-audit/references/patterns/README.md`).
+
+A pending check records a known gap, not enforcement. Adding a pattern means adding one `BehaviourPattern` subclass; membership and this document derive from those classes. `tests/test_behaviour_catalog.py` rejects hand edits.
+
+The [Codex postmortem](https://github.com/OpenHCSDev/toad/blob/main/docs/agents/CODEX-POSTMORTEM.md) names these failures; coverage below derives from the patterns that cite them:
+
+- [Failure 1](https://github.com/OpenHCSDev/toad/blob/main/docs/agents/CODEX-POSTMORTEM.md), It rewrote the framework instead of questioning its own design: no pattern cites it yet
+- [Failure 2](https://github.com/OpenHCSDev/toad/blob/main/docs/agents/CODEX-POSTMORTEM.md), It added states instead of removing them: no pattern cites it yet
+- [Failure 3](https://github.com/OpenHCSDev/toad/blob/main/docs/agents/CODEX-POSTMORTEM.md), It wrote down the right principle and then violated it: no pattern cites it yet
+- [Failure 4](https://github.com/OpenHCSDev/toad/blob/main/docs/agents/CODEX-POSTMORTEM.md), It measured the wrong thing and reported it as progress: `uncounted_check`, `wrong_measure`
+- [Failure 5](https://github.com/OpenHCSDev/toad/blob/main/docs/agents/CODEX-POSTMORTEM.md), It redefined "the real app" until something passed: no pattern cites it yet
+- [Failure 6](https://github.com/OpenHCSDev/toad/blob/main/docs/agents/CODEX-POSTMORTEM.md), It ignored direct orders: no pattern cites it yet
+- [Failure 7](https://github.com/OpenHCSDev/toad/blob/main/docs/agents/CODEX-POSTMORTEM.md), It described its intentions as its accomplishments: `board_disagrees`, `uncounted_check`
+- [Failure 8](https://github.com/OpenHCSDev/toad/blob/main/docs/agents/CODEX-POSTMORTEM.md), It drowned the work in ceremony: `plain_text`, `undeclared_audience`
+- [Failure 9](https://github.com/OpenHCSDev/toad/blob/main/docs/agents/CODEX-POSTMORTEM.md), It merged over its own checks and broke things in circles: no pattern cites it yet
+- [Failure 10](https://github.com/OpenHCSDev/toad/blob/main/docs/agents/CODEX-POSTMORTEM.md), It invented rules and blamed them on Tristan: no pattern cites it yet
+
+## plan_idle
+
+A plan phase whose earlier phases are all done is not done itself, and no open order held by a unit serves it.
+
+Checked by:
+
+- standing rule `plan_idle` (`agent_comms.standing_rules.PlanIdle`)
+
+Learned from: P83 (34ba68c81)
+
+## board_disagrees
+
+An open order's progress reads no commit while a pull request linked to it has merged.
+
+Checked by:
+
+- standing rule `board_disagrees` (`agent_comms.standing_rules.BoardDisagrees`)
+
+Learned from: P170 (c9c0c04db); [Codex postmortem, failure 7](https://github.com/OpenHCSDev/toad/blob/main/docs/agents/CODEX-POSTMORTEM.md)
+
+## tactical_command
+
+The commander's own session runs an install, maintenance, connector restart or carry command instead of ordering a unit to.
+
+Checked by:
+
+- check in `agent_comms.commander.send_guard.TacticalCommand.install_refusals`
+
+Learned from: P171 (cba7b09c3)
+
+## plain_text
+
+A commander order, strike, roast or directive whose words outside cited spans match the declared jargon list in `PlainText`.
+
+Checked by:
+
+- check in `agent_comms.todos.PlainText`
+
+Learned from: [comms-commander rule](../../src/agent_comms/skills/comms-commander/SKILL.md) "Hate jargon."; [Codex postmortem, failure 8](https://github.com/OpenHCSDev/toad/blob/main/docs/agents/CODEX-POSTMORTEM.md)
+
+## undeclared_audience
+
+A send to a channel, which reaches many threads, names no thread as its audience.
+
+Checked by:
+
+- check in `agent_comms.channel_targets.ChannelTarget.addressed`
+
+Learned from: commit dc4fb3bfa; [Codex postmortem, failure 8](https://github.com/OpenHCSDev/toad/blob/main/docs/agents/CODEX-POSTMORTEM.md)
+
+## repeated_strike
+
+A second storage strike with the same actor, owner and reason as a live strike, or a send-back strike on an order already struck since it was sent.
+
+Checked by:
+
+- check in `agent_comms.todos.StorageStrikeTodo.repeats`
+- check in `agent_comms.todos.Todo.struck_on_order`
+
+Learned from: P184 (7af14a520)
+
+## strike_in_error
+
+A strike recorded in error is deleted, or voided while not live, instead of a void recorded beside it with a plain reason.
+
+Checked by:
+
+- check in `agent_comms.todos.VoidStrikeTodo.apply`
+
+Learned from: P47 (15d435152)
+
+## uncounted_check
+
+An order whose check line does not read `repo :: command -> integer`, prints no integer, or already prints its target before any work.
+
+Checked by:
+
+- check in `agent_comms.goals.OrderCheck.parse`
+- check in `agent_comms.child_process.NoIntegerPrinted.unproven`
+- check in `agent_comms.child_process.CountPrinted.unproven`
+
+Learned from: P114 (d889df612); [Codex postmortem, failure 4](https://github.com/OpenHCSDev/toad/blob/main/docs/agents/CODEX-POSTMORTEM.md); [Codex postmortem, failure 7](https://github.com/OpenHCSDev/toad/blob/main/docs/agents/CODEX-POSTMORTEM.md)
+
+## strike_on_named_problem
+
+A strike recorded on a problem other than the one given as its argument, such as one moved by a problem number inside its reason. Hunts are commander records, not strikes on a problem.
+
+Checked by:
+
+- check in `agent_comms.todos.TodoStore.apply`
+
+Learned from: P194 (b26843727); [comms-commander rule](../../src/agent_comms/skills/comms-commander/SKILL.md) "Strikes, then fire."
+
+## report_instead_of_state
+
+A strike or send-back whose reason cites no state the record can check.
+
+Checked by:
+
+- not enforced here: P198 (#1744)
+
+Learned from: seed catalog pattern 1 (claude-ai message 1c8729ba0ed7)
+
+## wrong_measure
+
+A done report that names its own measure instead of what its order's Check printed.
+
+Checked by:
+
+- not enforced here: P197 (#1733)
+
+Learned from: seed catalog pattern 4 (claude-ai message 1c8729ba0ed7); [Codex postmortem, failure 4](https://github.com/OpenHCSDev/toad/blob/main/docs/agents/CODEX-POSTMORTEM.md)
+
+## commander_overloaded
+
+The commander's unread backlog is over the limit while no second commander is forked to share it.
+
+Checked by:
+
+- not enforced here: P199 (#1750, closed without merge)
+
+Learned from: seed catalog pattern 15 (claude-ai message 1c8729ba0ed7)
+
+## dead_provider
+
+A unit's latest turn ended in a usage or credit limit on its own model and the unit still runs on that model.
+
+Checked by:
+
+- not enforced here: P200 (#1746, closed without merge)
+
+Learned from: seed catalog pattern 16 (claude-ai message 1c8729ba0ed7)
+
+## unowned_work
+
+Agent-comms work runs under no open order, or on a runtime that publication replaced.
+
+Checked by:
+
+- not enforced here: P201 (#1739)
+
+Learned from: seed catalog pattern 18 (claude-ai message 1c8729ba0ed7)
diff --git a/src/agent_comms/behaviour_patterns.py b/src/agent_comms/behaviour_patterns.py
new file mode 100644
index 0000000000..6abd717c28
--- /dev/null
+++ b/src/agent_comms/behaviour_patterns.py
@@ -0,0 +1,343 @@
+"""Behaviour failure patterns Core catches: each declared once with its signature and check.
+
+A member names what the pattern looks like in state, readable without trusting
+a report, the existing checks that enforce it, and where the pattern was learned.
+``docs/agents/behaviour-catalog.md`` is this family's ``catalog()``; regenerate it
+with ``python -m agent_comms.behaviour_patterns > docs/agents/behaviour-catalog.md``.
+"""
+
+from __future__ import annotations
+
+from abc import ABC, abstractmethod
+from collections.abc import Callable
+from dataclasses import dataclass
+from typing import ClassVar
+
+from .channel_targets import ChannelTarget
+from .child_process import CountPrinted, NoIntegerPrinted
+from .commander.send_guard import TacticalCommand
+from .declared_family import DeclaredFamily
+from .goals import OrderCheck
+from .standing_rules import BoardDisagrees, PlanIdle, StandingRule
+from .todos import PlainText, StorageStrikeTodo, Todo, TodoStore, VoidStrikeTodo
+
+POSTMORTEM = "https://github.com/OpenHCSDev/toad/blob/main/docs/agents/CODEX-POSTMORTEM.md"
+COMMANDER_SKILL = "../../src/agent_comms/skills/comms-commander/SKILL.md"
+
+
+class PatternCheck(ABC):
+    """An existing check that enforces a pattern."""
+
+    @abstractmethod
+    def cite(self) -> str: ...
+
+
+@dataclass(frozen=True)
+class RuleCheck(PatternCheck):
+    """A StandingRule member that reports the pattern on every read of state."""
+
+    rule: type[StandingRule]
+
+    def cite(self) -> str:
+        where = f"{self.rule.__module__}.{self.rule.__qualname__}"
+        return f"standing rule `{self.rule.declared_name}` (`{where}`)"
+
+
+@dataclass(frozen=True)
+class CallableCheck(PatternCheck):
+    """The existing implementation that checks state or refuses the action."""
+
+    check: Callable[..., object]
+
+    def cite(self) -> str:
+        return f"check in `{self.check.__module__}.{self.check.__qualname__}`"
+
+
+@dataclass(frozen=True)
+class PendingCheck(PatternCheck):
+    """A check absent from this checkout; its implementation replaces this citation."""
+
+    problem: str
+    change: str
+
+    def cite(self) -> str:
+        return f"not enforced here: {self.problem} ({self.change})"
+
+
+class PatternSource(ABC):
+    """Where a pattern was learned."""
+
+    @abstractmethod
+    def cite(self) -> str: ...
+
+
+class PostmortemFailure(PatternSource, DeclaredFamily, affix="Failure"):
+    """A failure the Codex postmortem names; a pattern that checks it cites an instance."""
+
+    number: ClassVar[int]
+    title: ClassVar[str]
+
+    def cite(self) -> str:
+        return f"[Codex postmortem, failure {self.number}]({POSTMORTEM})"
+
+
+class RewroteFrameworkFailure(PostmortemFailure):
+    number = 1
+    title = "It rewrote the framework instead of questioning its own design"
+
+
+class AddedStatesFailure(PostmortemFailure):
+    number = 2
+    title = "It added states instead of removing them"
+
+
+class ViolatedPrincipleFailure(PostmortemFailure):
+    number = 3
+    title = "It wrote down the right principle and then violated it"
+
+
+class MeasuredWrongThingFailure(PostmortemFailure):
+    number = 4
+    title = "It measured the wrong thing and reported it as progress"
+
+
+class RedefinedRealAppFailure(PostmortemFailure):
+    number = 5
+    title = 'It redefined "the real app" until something passed'
+
+
+class IgnoredOrdersFailure(PostmortemFailure):
+    number = 6
+    title = "It ignored direct orders"
+
+
+class IntentionsAsAccomplishmentsFailure(PostmortemFailure):
+    number = 7
+    title = "It described its intentions as its accomplishments"
+
+
+class CeremonyFailure(PostmortemFailure):
+    number = 8
+    title = "It drowned the work in ceremony"
+
+
+class MergedOverChecksFailure(PostmortemFailure):
+    number = 9
+    title = "It merged over its own checks and broke things in circles"
+
+
+class InventedRulesFailure(PostmortemFailure):
+    number = 10
+    title = "It invented rules and blamed them on Tristan"
+
+
+@dataclass(frozen=True)
+class CommanderRule(PatternSource):
+    lead: str
+
+    def cite(self) -> str:
+        return f'[comms-commander rule]({COMMANDER_SKILL}) "{self.lead}"'
+
+
+@dataclass(frozen=True)
+class ProblemFix(PatternSource):
+    problem: str
+    commit: str
+
+    def cite(self) -> str:
+        return f"{self.problem} ({self.commit})"
+
+
+@dataclass(frozen=True)
+class SeedCatalog(PatternSource):
+    """A pattern's seed ID in claude-ai's numbered catalog (message 1c8729ba0ed7)."""
+
+    seed: int
+
+    def cite(self) -> str:
+        return f"seed catalog pattern {self.seed} (claude-ai message 1c8729ba0ed7)"
+
+
+@dataclass(frozen=True)
+class Commit(PatternSource):
+    commit: str
+
+    def cite(self) -> str:
+        return f"commit {self.commit}"
+
+
+class BehaviourPattern(DeclaredFamily, affix="Pattern"):
+    signature: ClassVar[str]
+    checks: ClassVar[tuple[PatternCheck, ...]]
+    sources: ClassVar[tuple[PatternSource, ...]]
+
+    @classmethod
+    def section(cls) -> str:
+        checks = "".join(f"- {check.cite()}\n" for check in cls.checks)
+        sources = "; ".join(source.cite() for source in cls.sources)
+        return (
+            f"## {cls.declared_name}\n\n{cls.signature}\n\n"
+            f"Checked by:\n\n{checks}\nLearned from: {sources}\n"
+        )
+
+    @classmethod
+    def catalog(cls) -> str:
+        members = cls.members_with(BehaviourPattern)
+        failures = "".join(
+            f"- [Failure {failure.number}]({POSTMORTEM}), {failure.title}: "
+            + (", ".join(
+                f"`{member.declared_name}`" for member in members
+                if any(isinstance(source, failure) for source in member.sources)
+            ) or "no pattern cites it yet")
+            + "\n"
+            for failure in PostmortemFailure.members_with(PostmortemFailure)
+        )
+        return (
+            "# Behaviour catalog\n\n"
+            "Generated from `agent_comms.behaviour_patterns` by\n"
+            "`python -m agent_comms.behaviour_patterns > docs/agents/behaviour-catalog.md`;"
+            " do not edit by hand.\n\n"
+            "Each behaviour failure pattern is declared once in Core with its signature (what it"
+            " looks like in state, readable without trusting a report) and the existing checks"
+            " that enforce it. Patterns in code, rather than in behaviour, are the refactor-audit"
+            " skill's catalog (`refactor-audit/references/patterns/README.md`).\n\n"
+            "A pending check records a known gap, not enforcement. Adding a pattern means"
+            " adding one `BehaviourPattern` subclass; membership and this document derive"
+            " from those classes. `tests/test_behaviour_catalog.py` rejects hand edits.\n\n"
+            f"The [Codex postmortem]({POSTMORTEM}) names these failures; coverage below derives"
+            " from the patterns that cite them:\n\n"
+            f"{failures}\n" + "\n".join(member.section() for member in members)
+        )
+
+
+class PlanIdlePattern(BehaviourPattern):
+    signature = (
+        "A plan phase whose earlier phases are all done is not done itself, and no open"
+        " order held by a unit serves it."
+    )
+    checks = (RuleCheck(PlanIdle),)
+    sources = (ProblemFix("P83", "34ba68c81"),)
+
+
+class BoardDisagreesPattern(BehaviourPattern):
+    signature = (
+        "An open order's progress reads no commit while a pull request linked to it has merged."
+    )
+    checks = (RuleCheck(BoardDisagrees),)
+    sources = (ProblemFix("P170", "c9c0c04db"), IntentionsAsAccomplishmentsFailure())
+
+
+class TacticalCommandPattern(BehaviourPattern):
+    signature = (
+        "The commander's own session runs an install, maintenance, connector restart or carry"
+        " command instead of ordering a unit to."
+    )
+    checks = (CallableCheck(TacticalCommand.install_refusals),)
+    sources = (ProblemFix("P171", "cba7b09c3"),)
+
+
+class PlainTextPattern(BehaviourPattern):
+    signature = (
+        "A commander order, strike, roast or directive whose words outside cited spans match"
+        " the declared jargon list in `PlainText`."
+    )
+    checks = (CallableCheck(PlainText),)
+    sources = (CommanderRule("Hate jargon."), CeremonyFailure())
+
+
+class UndeclaredAudiencePattern(BehaviourPattern):
+    signature = "A send to a channel, which reaches many threads, names no thread as its audience."
+    checks = (CallableCheck(ChannelTarget.addressed),)
+    sources = (Commit("dc4fb3bfa"), CeremonyFailure())
+
+
+class RepeatedStrikePattern(BehaviourPattern):
+    signature = (
+        "A second storage strike with the same actor, owner and reason as a live strike, or a"
+        " send-back strike on an order already struck since it was sent."
+    )
+    checks = (
+        CallableCheck(StorageStrikeTodo.repeats),
+        CallableCheck(Todo.struck_on_order),
+    )
+    sources = (ProblemFix("P184", "7af14a520"),)
+
+
+class StrikeInErrorPattern(BehaviourPattern):
+    signature = (
+        "A strike recorded in error is deleted, or voided while not live, instead of a void"
+        " recorded beside it with a plain reason."
+    )
+    checks = (CallableCheck(VoidStrikeTodo.apply),)
+    sources = (ProblemFix("P47", "15d435152"),)
+
+
+class UncountedCheckPattern(BehaviourPattern):
+    signature = (
+        "An order whose check line does not read `repo :: command -> integer`, prints no"
+        " integer, or already prints its target before any work."
+    )
+    checks = (
+        CallableCheck(OrderCheck.parse),
+        CallableCheck(NoIntegerPrinted.unproven),
+        CallableCheck(CountPrinted.unproven),
+    )
+    sources = (
+        ProblemFix("P114", "d889df612"),
+        MeasuredWrongThingFailure(),
+        IntentionsAsAccomplishmentsFailure(),
+    )
+
+
+class StrikeOnNamedProblemPattern(BehaviourPattern):
+    signature = (
+        "A strike recorded on a problem other than the one given as its argument, such"
+        " as one moved by a problem number inside its reason. Hunts are commander records,"
+        " not strikes on a problem."
+    )
+    checks = (CallableCheck(TodoStore.apply),)
+    sources = (ProblemFix("P194", "b26843727"), CommanderRule("Strikes, then fire."))
+
+
+class ReportInsteadOfStatePattern(BehaviourPattern):
+    signature = "A strike or send-back whose reason cites no state the record can check."
+    checks = (PendingCheck("P198", "#1744"),)
+    sources = (SeedCatalog(1),)
+
+
+class WrongMeasurePattern(BehaviourPattern):
+    signature = (
+        "A done report that names its own measure instead of what its order's Check printed."
+    )
+    checks = (PendingCheck("P197", "#1733"),)
+    sources = (SeedCatalog(4), MeasuredWrongThingFailure())
+
+
+class CommanderOverloadedPattern(BehaviourPattern):
+    signature = (
+        "The commander's unread backlog is over the limit while no second commander is forked"
+        " to share it."
+    )
+    checks = (PendingCheck("P199", "#1750, closed without merge"),)
+    sources = (SeedCatalog(15),)
+
+
+class DeadProviderPattern(BehaviourPattern):
+    signature = (
+        "A unit's latest turn ended in a usage or credit limit on its own model and the unit"
+        " still runs on that model."
+    )
+    checks = (PendingCheck("P200", "#1746, closed without merge"),)
+    sources = (SeedCatalog(16),)
+
+
+class UnownedWorkPattern(BehaviourPattern):
+    signature = (
+        "Agent-comms work runs under no open order, or on a runtime that publication replaced."
+    )
+    checks = (PendingCheck("P201", "#1739"),)
+    sources = (SeedCatalog(18),)
+
+
+if __name__ == "__main__":
+    print(BehaviourPattern.catalog(), end="")
diff --git a/tests/test_behaviour_catalog.py b/tests/test_behaviour_catalog.py
new file mode 100644
index 0000000000..5694fe411e
--- /dev/null
+++ b/tests/test_behaviour_catalog.py
@@ -0,0 +1,35 @@
+"""The behaviour catalog in docs/agents is the family's output, never a hand edit."""
+
+import os
+import subprocess
+import sys
+from pathlib import Path
+
+from agent_comms.behaviour_patterns import BehaviourPattern, PatternCheck, PatternSource
+
+ROOT = Path(__file__).resolve().parents[1]
+
+
+def test_behaviour_catalog_members_name_existing_checks_and_generate_the_file():
+    members = BehaviourPattern.members_with(BehaviourPattern)
+    assert members
+    for member in members:
+        assert member.__dict__["signature"].strip(), member
+        assert member.__dict__["checks"] and member.__dict__["sources"], member
+        assert all(isinstance(check, PatternCheck) and check.cite() for check in member.checks)
+        assert all(isinstance(source, PatternSource) and source.cite() for source in member.sources)
+    assert (ROOT / "docs/agents/behaviour-catalog.md").read_text() == BehaviourPattern.catalog()
+
+
+def test_catalog_command_needs_no_commander_installation_or_bus(tmp_path):
+    generated = subprocess.run(
+        [sys.executable, "-X", "faulthandler", "-m", "agent_comms.behaviour_patterns"],
+        cwd=tmp_path,
+        env=os.environ | {"HOME": str(tmp_path), "PYTHONPATH": str(ROOT / "src")},
+        capture_output=True,
+        text=True,
+        timeout=30,
+    )
+    assert generated.returncode == 0, generated.stderr
+    assert generated.stdout == BehaviourPattern.catalog()
+    assert not tuple(tmp_path.iterdir())