@@ -0,0 +1,176 @@
+#!/usr/bin/env python3
+"""Prose punctuation conformance hook for tiny-blocks PHP libraries.
+
+Self-contained PostToolUse hook on Edit|Write|MultiEdit. Verifies prose punctuation:
+no em-dash, en-dash, or ` -- ` as a clause separator in Markdown prose or
+PHP comments, plus no `;` separator in Markdown. The checks read raw text only, so
+this script carries no PHP lexer. Markdown files route to the prose check, PHP
+sources to the comment check.
+
+Control flow uses guard clauses only and nesting never exceeds two levels. Reports
+violations to stderr and exits 2 to prompt Claude with feedback; exits 0 silently if
+no violations or the file is out of scope.
+"""
+
+import json
+import re
+import sys
+from dataclasses import dataclass
+from pathlib import Path
+from typing import Final
+
+# --- Configuration ----------------------------------------------------------
+
+# In-scope files: PHP sources under src/ or tests/, plus any Markdown file.
+SCOPE_PATTERN: Final = re.compile(r"(^|/)(src|tests)/.+\.php$")
+MARKDOWN_PATTERN: Final = re.compile(r"\.md$")
+
+# Prohibited prose punctuation as clause separators. Em-dash U+2014, en-dash U+2013,
+# spaced double hyphen, and (Markdown only) the semicolon.
+PROSE_PUNCTUATION: Final = re.compile(r"[\u2014\u2013]| -- |;")
+PROSE_DASHES: Final = re.compile(r"[\u2014\u2013]| -- ")
+FENCE: Final = re.compile(r"^\s*```")
+PHP_COMMENT: Final = re.compile(r"/\*.*?\*/|//[^\n]*|#(?!\[)[^\n]*", re.DOTALL)
+INLINE_CODE: Final = re.compile(r"`[^`]*`")
+
+MAX_ERRORS_REPORTED = 30
+
+
+# --- Types --------------------------------------------------------------------
+
+
+@dataclass(frozen=True)
+class Violation:
+    """One style violation at a source position."""
+
+    line: int
+    path: str
+    message: str
+
+    def __str__(self) -> str:
+        return f"{self.path}:{self.line}: {self.message}"
+
+
+@dataclass(frozen=True)
+class FileUnit:
+    """One file under analysis: its path and raw text. No lexing needed here."""
+
+    path: str
+    text: str
+
+
+# --- Checks -------------------------------------------------------------------
+
+
+def is_markdown(path: str) -> bool:
+    """Whether the path is a Markdown file, routed to the Markdown prose check."""
+    return bool(MARKDOWN_PATTERN.search(path))
+
+
+def markdown_violations(unit: FileUnit) -> tuple[Violation, ...]:
+    """No `;`, em-dash, en-dash, or ` -- ` as a clause
+    separator in Markdown prose. Fenced code and table rows are exempt."""
+    violations = []
+    in_fence = False
+    for number, line in enumerate(unit.text.split("\n"), start=1):
+        if FENCE.match(line):
+            in_fence = not in_fence
+            continue
+
+        if in_fence or "|" in line:
+            continue
+
+        if PROSE_PUNCTUATION.search(INLINE_CODE.sub("", line)):
+            violations.append(Violation(
+                line=number,
+                path=unit.path,
+                message=(
+                    "prohibited prose punctuation (`;`, em-dash, en-dash, or ` -- `), "
+                    "split the sentence or use a comma, colon, or parentheses"
+                ),
+            ))
+    return tuple(violations)
+
+
+def comment_violations(unit: FileUnit) -> tuple[Violation, ...]:
+    """In PHPDoc and comments: no em-dash, en-dash,
+    or ` -- ` as a separator. The `;` is not checked in PHP comments (it terminates
+    statements in commented code)."""
+    violations = []
+    for match in PHP_COMMENT.finditer(unit.text):
+        if PROSE_DASHES.search(INLINE_CODE.sub("", match.group(0))):
+            violations.append(Violation(
+                line=unit.text.count("\n", 0, match.start()) + 1,
+                path=unit.path,
+                message=(
+                    "prohibited prose punctuation (em-dash, en-dash, or ` -- `) in a "
+                    "comment"
+                ),
+            ))
+    return tuple(violations)
+
+
+def punctuation_violations(unit: FileUnit) -> tuple[Violation, ...]:
+    """Punctuation violations for one file: Markdown prose for `.md`, comments otherwise."""
+    if is_markdown(unit.path):
+        return markdown_violations(unit)
+    return comment_violations(unit)
+
+
+# --- Shell --------------------------------------------------------------------
+
+
+def requested_paths() -> list[Path]:
+    """The paths to verify, from argv or from the hook's stdin payload."""
+    if len(sys.argv) > 1:
+        return [Path(argument) for argument in sys.argv[1:]]
+    try:
+        payload = json.load(sys.stdin)
+    except ValueError:
+        return []
+
+    file_path = (payload.get("tool_input") or {}).get("file_path")
+
+    if isinstance(file_path, str):
+        return [Path(file_path)]
+    return []
+
+
+def in_scope(path: Path) -> bool:
+    """Whether the path is a PHP source or any Markdown this hook covers."""
+    posix = path.as_posix()
+    matched = SCOPE_PATTERN.search(posix) or MARKDOWN_PATTERN.search(posix)
+    return bool(matched) and path.is_file()
+
+
+def file_violations(path: Path) -> tuple[Violation, ...]:
+    """The punctuation violations for one file."""
+    unit = FileUnit(
+        path=path.as_posix(),
+        text=path.read_text(errors="replace", encoding="utf-8"),
+    )
+    return punctuation_violations(unit)
+
+
+def main() -> int:
+    violations = [
+        violation
+        for path in requested_paths()
+        if in_scope(path)
+        for violation in file_violations(path)
+    ]
+
+    if not violations:
+        return 0
+
+    for violation in violations[:MAX_ERRORS_REPORTED]:
+        print(violation, file=sys.stderr)
+    overflow = len(violations) - MAX_ERRORS_REPORTED
+
+    if overflow > 0:
+        print(f"... and {overflow} more violations", file=sys.stderr)
+    return 2
+
+
+if __name__ == "__main__":
+    sys.exit(main())
@@ -0,0 +1,147 @@
+---
+description: Folder structure, public API boundary, and Internal/ semantics for PHP libraries.
+paths:
+    - "src/**/*.php"
+---
+
+# Architecture
+
+Covers the physical layout of the library. Folder structure, the boundary between public API and
+implementation detail, and where each type of class lives. Semantic rules (value objects,
+exceptions, enums, complexity, nomenclature) live in `php-library-modeling.md`. Code style lives
+in `php-library-code-style.md`.
+
+## Pre-output checklist
+
+Verify every item before producing or relocating any file. If any item fails, revise before
+outputting.
+
+1. None of the following folder names exist in `src/`: `Models/`, `Entities/`, `ValueObjects/`,
+   `Enums/`, `Domain/`. They carry no semantic content and conflate technical role with domain
+   meaning.
+2. The `src/` root contains only interfaces, extension points, public enums, thin orchestration
+   classes, and primary implementations or façades. Substantial logic (algorithms, state machines,
+   I/O) lives in `src/Internal/`, never at the root.
+3. `src/Internal/` is implementation detail and not part of the public API. Breaking changes
+   inside `src/Internal/` are not semver-breaking.
+4. Consumers must not reference, extend, or depend on any type inside `src/Internal/`. The
+   namespace itself is the boundary.
+5. Public exception classes live in `src/Exceptions/`.
+6. Internal exception classes live in `src/Internal/Exceptions/`.
+7. Public enums live at the `src/` root or inside a public `<ConceptGroup>/` folder. Enums used
+   only by internals live in `src/Internal/`.
+8. Public interfaces live at the `src/` root or inside a public `<ConceptGroup>/` folder.
+9. A `<ConceptGroup>/` folder at the `src/` root groups related public types under a shared
+   concept. Each group has its own namespace and is part of the public API.
+10. `<ConceptGroup>/` is optional. Use it only when the library exposes several coherent groups of
+    types (for example, aggregates and events) rather than a flat set of types around a single
+    concept.
+11. Test fixtures representing domain concepts live in `tests/Models/`. Test doubles for system
+    boundaries live at the root of `tests/Unit/` or `tests/Integration/`. No dedicated `Mocks/`
+    or `Doubles/` subdirectory exists. Vendor compatibility (driver) tests, verifying the
+    library against specific external libraries/frameworks, are optional and have no `src/`
+    counterpart. They exist only as tests, under `tests/Integration/Drivers/<Vendor>/`,
+    grouped by vendor. Never a top-level `Drivers/` under `tests/`.
+12. The `tests/Integration/` folder exists only when the library interacts with external
+    infrastructure (filesystem, database, network). Otherwise, the folder is absent.
+
+## Folder structure
+
+Canonical layout for a PHP library in the tiny-blocks ecosystem.
+
+```
+src/
+├── <PublicInterface>.php     # public contract at root
+├── <Implementation>.php      # main implementation or extension point at root
+├── <PublicEnum>.php          # public enum at root
+├── <ConceptGroup>/           # public folder grouping related public types under a shared concept
+│   ├── <PublicType>.php
+│   └── ...
+├── Internal/                 # implementation details, not part of the public API
+│   ├── <Collaborator>.php
+│   └── Exceptions/           # internal exception classes
+└── Exceptions/               # public exception classes
+
+tests/
+├── Models/                   # domain fixtures reused across tests
+├── Unit/                     # unit tests targeting the public API
+│   ├── <SomeMock>.php        # test doubles at root of Unit/
+│   └── <SomeSpy>.php
+└── Integration/              # only present when the library interacts with infrastructure
+    ├── Drivers/              # only present when the library exposes vendor-specific drivers
+    │   └── <Vendor>/         # tests against one specific third-party implementation
+    └── <SomeMock>.php        # test doubles at root of Integration/ when needed
+```
+
+Never use `Models/`, `Entities/`, `ValueObjects/`, `Enums/`, or `Domain/` as folder names. They
+carry no semantic content and describe technical role instead of domain meaning.
+
+## Public API boundary
+
+The `src/` root is the contract. Everything at the root, plus everything inside public
+`<ConceptGroup>/` folders and the public `Exceptions/` folder, is what consumers depend on. Changes
+to these types follow semver rules.
+
+`src/Internal/` is implementation detail. The namespace itself signals the boundary. Consumers
+must not depend on any type inside `src/Internal/`. Breaking changes inside `src/Internal/` are
+not semver-breaking for the library.
+
+### What lives at the public boundary
+
+- Interfaces that define contracts for consumers.
+- Extension points designed to be subclassed or composed by consumers.
+- Public enums and value objects consumers manipulate directly.
+- Thin orchestration classes that wire collaborators together without containing substantial logic.
+- Public exception classes consumers may catch.
+
+### What lives in `src/Internal/`
+
+- Algorithms, state machines, and complex transformations.
+- Adapters for I/O (filesystem, network, database).
+- Collaborators that exist purely to break a public class into testable units.
+- Implementation details that may change between minor or patch releases.
+- Internal exception classes raised by collaborators.
+
+## Reference examples
+
+### Small library with flat root
+
+```
+src/
+├── Timezone.php              # public value object
+├── Timezones.php             # public collection
+├── Clock.php                 # public interface
+└── Internal/
+    ├── SystemClock.php       # default Clock implementation
+    └── Exceptions/
+        └── InvalidTimezone.php
+```
+
+Everything lives at the root or inside `Internal/`. No `<ConceptGroup>/` folders. Suitable when
+the library exposes a small, cohesive set of types around a single concept.
+
+### Library with public concept groups
+
+```
+src/
+├── ValueObject.php                 # public extension point at root
+├── Aggregate/                      # public namespace grouping aggregate types
+│   ├── AggregateRoot.php
+│   ├── EventualAggregateRoot.php
+│   └── ModelVersion.php
+├── Event/                          # public namespace grouping event types
+│   ├── EventRecord.php
+│   ├── EventRecords.php
+│   └── SequenceNumber.php
+├── Internal/
+│   ├── DefaultModelVersionResolver.php
+│   └── Exceptions/
+│       └── InvalidSequenceNumber.php
+└── Exceptions/
+    └── EventRecordingFailure.php
+```
+
+`Aggregate/` and `Event/` are public folders at the root, each grouping a coherent set of public
+types under one shared concept. Consumers import directly, for example
+`TinyBlocks\<LibName>\Aggregate\AggregateRoot`. Suitable when the library exposes several distinct
+concept areas, each with its own set of related types.