diff --git a/documentation/usage.es.md b/documentation/usage.es.md
index 767c4d3..baaa98d 100644
--- a/documentation/usage.es.md
+++ b/documentation/usage.es.md
@@ -149,6 +149,14 @@ rules:
 | `severity` | no | `blocking` (por defecto), `warning` o `advisory` (ver abajo) |
 | `target` | no | `files` (por defecto) o `commit-msg` (ver abajo) |
 
+> **Autocompletado y validación en el editor.** `.bec/rules.yaml` tiene un
+> [JSON Schema](../schema/rules.schema.json) publicado. `becwright init` escribe
+> una línea `# yaml-language-server: $schema=…` al inicio del archivo, así los
+> editores con language server de YAML (la extensión YAML de VS Code, los IDEs
+> de JetBrains) autocompletan los campos y marcan un typo (`pathss:`,
+> `severity: blockng`) mientras escribís. Agregá esa línea a mano en un archivo
+> de reglas preexistente para obtener lo mismo.
+
 **`schema_version`** es una clave opcional de nivel superior (no un campo de
 regla). Sella la versión de formato del archivo; cuando falta se trata como `1`,
 así que los archivos existentes siguen funcionando. `becwright init` la escribe,
diff --git a/documentation/usage.md b/documentation/usage.md
index 59ac159..8de2751 100644
--- a/documentation/usage.md
+++ b/documentation/usage.md
@@ -148,6 +148,13 @@ rules:
 | `severity` | no | `blocking` (default), `warning`, or `advisory` (see below) |
 | `target` | no | `files` (default) or `commit-msg` (see below) |
 
+> **Editor autocompletion and validation.** `.bec/rules.yaml` has a published
+> [JSON Schema](../schema/rules.schema.json). `becwright init` writes a
+> `# yaml-language-server: $schema=…` line at the top of the file, so editors
+> with a YAML language server (VS Code's YAML extension, JetBrains IDEs)
+> autocomplete the fields and flag a typo (`pathss:`, `severity: blockng`) as
+> you type. Add that line by hand to a pre-existing rules file to get the same.
+
 **`schema_version`** is an optional top-level key (not a rule field). It stamps
 the format version of the file; when absent it is treated as `1`, so existing
 files keep working. `becwright init` writes it, and becwright refuses a file
diff --git a/pyproject.toml b/pyproject.toml
index 6f825eb..2503f86 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -43,7 +43,8 @@ classifiers = [
 becwright = "becwright.cli:main"
 
 [project.optional-dependencies]
-dev = ["pytest>=8", "pytest-cov>=5", "mcp>=1.2"]
+# jsonschema is test-only: it validates schema/rules.schema.json against examples.
+dev = ["pytest>=8", "pytest-cov>=5", "mcp>=1.2", "jsonschema>=4"]
 # Used to freeze the standalone binary distributed via npm (see packaging/).
 build = ["pyinstaller>=6"]
 # MCP server for AI agents: `becwright mcp` (see src/becwright/mcp_server.py).
diff --git a/schema/rules.schema.json b/schema/rules.schema.json
new file mode 100644
index 0000000..d4c4a97
--- /dev/null
+++ b/schema/rules.schema.json
@@ -0,0 +1,72 @@
+{
+  "$schema": "http://json-schema.org/draft-07/schema#",
+  "$id": "https://raw.githubusercontent.com/DataDave-Dev/becwright/main/schema/rules.schema.json",
+  "title": "becwright rules",
+  "description": "Schema for .bec/rules.yaml — the rules becwright enforces on every commit. Field reference: https://github.com/DataDave-Dev/becwright/blob/main/documentation/usage.md",
+  "type": "object",
+  "additionalProperties": false,
+  "properties": {
+    "schema_version": {
+      "type": "integer",
+      "minimum": 1,
+      "description": "Format version of this file; absent means 1. becwright refuses a file stamped newer than it understands."
+    },
+    "rules": {
+      "type": "array",
+      "description": "The rules (BECs) enforced on every commit.",
+      "items": { "$ref": "#/definitions/rule" }
+    }
+  },
+  "definitions": {
+    "rule": {
+      "type": "object",
+      "additionalProperties": false,
+      "required": ["id", "check"],
+      "properties": {
+        "id": {
+          "type": "string",
+          "minLength": 1,
+          "description": "Unique rule id, e.g. no-token-in-logs."
+        },
+        "intent": {
+          "type": "string",
+          "description": "What the rule asks for — the 'bound' half of the BEC."
+        },
+        "why_it_matters": {
+          "type": "string",
+          "description": "Why the rule exists; shown the moment the rule fails."
+        },
+        "rejected_alternatives": {
+          "type": "array",
+          "items": { "type": "string" },
+          "description": "Context: approaches that were considered and dropped."
+        },
+        "paths": {
+          "type": "array",
+          "items": { "type": "string", "minLength": 1 },
+          "description": "Glob patterns of the files this rule applies to (e.g. src/**/*.py). Not needed for target: commit-msg rules."
+        },
+        "exclude": {
+          "type": "array",
+          "items": { "type": "string", "minLength": 1 },
+          "description": "Globs carved out of `paths` — vendored code, generated files, the check's own implementation."
+        },
+        "check": {
+          "type": "string",
+          "minLength": 1,
+          "description": "Shell command that runs the check: reads the file list on stdin, exits 0 (pass) or non-zero (fail). E.g. becwright run forbid --pattern '...'"
+        },
+        "severity": {
+          "enum": ["blocking", "warning", "advisory"],
+          "default": "blocking",
+          "description": "blocking = stops the commit | warning = deterministic finding, does not block | advisory = best-effort / non-deterministic, reports but never blocks."
+        },
+        "target": {
+          "enum": ["files", "commit-msg"],
+          "default": "files",
+          "description": "files = the changed files (default) | commit-msg = the commit message."
+        }
+      }
+    }
+  }
+}
diff --git a/src/becwright/cli.py b/src/becwright/cli.py
index fc7f409..118daf8 100644
--- a/src/becwright/cli.py
+++ b/src/becwright/cli.py
@@ -704,6 +704,7 @@ def _rules_from_claude_md(text: str, langs: list[str]) -> list[tuple[dict, str]]
 
 def _render_rules_yaml(rules: list[dict]) -> str:
     header = (
+        "# yaml-language-server: $schema=https://raw.githubusercontent.com/DataDave-Dev/becwright/main/schema/rules.schema.json\n"
         "# becwright rules - generated by `becwright init`. Tune them to your repo.\n"
         "# More rules: `becwright search` to list the catalog, `becwright add <name>` to install.\n"
         "# Docs: https://github.com/DataDave-Dev/becwright/tree/main/documentation\n"
diff --git a/tests/test_schema.py b/tests/test_schema.py
new file mode 100644
index 0000000..69bac83
--- /dev/null
+++ b/tests/test_schema.py
@@ -0,0 +1,80 @@
+import json
+from pathlib import Path
+
+import pytest
+import yaml
+
+from becwright import cli
+
+_SCHEMA_PATH = Path(__file__).resolve().parents[1] / "schema" / "rules.schema.json"
+_REPO_RULES = Path(__file__).resolve().parents[1] / ".bec" / "rules.yaml"
+
+jsonschema = pytest.importorskip("jsonschema")
+
+
+def _schema():
+    return json.loads(_SCHEMA_PATH.read_text(encoding="utf-8"))
+
+
+def _validate(data):
+    jsonschema.validate(data, _schema())
+
+
+def test_schema_is_valid_jsonschema():
+    jsonschema.Draft7Validator.check_schema(_schema())
+
+
+def test_valid_rules_file_passes():
+    _validate({
+        "schema_version": 1,
+        "rules": [{
+            "id": "no-token-in-logs",
+            "intent": "Tokens must never reach a log.",
+            "why_it_matters": "A token in the logs lets anyone steal a session.",
+            "rejected_alternatives": ["Redact at log time -> too easy to bypass"],
+            "paths": ["src/**/*.py"],
+            "exclude": ["src/logging_setup.py"],
+            "check": "becwright run no_token_in_logs",
+            "severity": "blocking",
+        }],
+    })
+
+
+def test_commit_msg_rule_needs_no_paths():
+    _validate({
+        "rules": [{
+            "id": "conventional-commits",
+            "target": "commit-msg",
+            "check": "becwright run require --pattern '^feat'",
+        }],
+    })
+
+
+def test_typoed_field_fails():
+    with pytest.raises(jsonschema.ValidationError):
+        _validate({
+            "rules": [{
+                "id": "x", "check": "true",
+                "pathss": ["**/*.py"],  # the typo the schema exists to catch
+            }],
+        })
+
+
+def test_invalid_severity_fails():
+    with pytest.raises(jsonschema.ValidationError):
+        _validate({"rules": [{"id": "x", "check": "true", "severity": "blockng"}]})
+
+
+def test_missing_check_fails():
+    with pytest.raises(jsonschema.ValidationError):
+        _validate({"rules": [{"id": "x", "paths": ["**/*.py"]}]})
+
+
+def test_generated_init_output_validates():
+    rendered = cli._render_rules_yaml(cli._starter_rules(["python", "ts"]))
+    assert rendered.startswith("# yaml-language-server: $schema=")
+    _validate(yaml.safe_load(rendered))
+
+
+def test_this_repos_rules_validate():
+    _validate(yaml.safe_load(_REPO_RULES.read_text(encoding="utf-8")))