feat(meta): add spec-validator tool

docs/labels-and-capabilities.md

@@ -187,6 +187,7 @@ Tools under [`tools/`](../tools/). Tools with two values (separated by
 | [`tools/skill-evals`](../tools/skill-evals/) | `capability:setup` + `capability:stats` | Eval harness for skills; the harness is setup infrastructure, the run output is governance evidence |
 | [`tools/skill-and-tool-validator`](../tools/skill-and-tool-validator/) | `capability:setup` | Skill-frontmatter and convention validator |
 | [`tools/spec-status-index`](../tools/spec-status-index/) | `capability:setup` + `capability:stats` | Index of spec / RFC implementation status — substrate that also doubles as a governance/stats view |
+| [`tools/spec-validator`](../tools/spec-validator/) | `capability:setup` | Spec-frontmatter and body-section validator — counterpart to `skill-and-tool-validator` for `tools/spec-loop/specs/` |
 | [`tools/vulnogram`](../tools/vulnogram/) | `capability:resolve` | ASF Vulnogram CVE-allocation client |
 
 A tool's capabilities are determined by its **use-case lifecycle

tools/spec-validator/README.md

@@ -0,0 +1,51 @@
+<!-- START doctoc generated TOC please keep comment here to allow auto update -->
+<!-- DON'T EDIT THIS SECTION, INSTEAD RE-RUN doctoc TO UPDATE -->
+**Table of Contents**  *generated with [DocToc](https://github.com/thlorenz/doctoc)*
+
+- [spec-validator](#spec-validator)
+  - [What it checks](#what-it-checks)
+  - [Usage](#usage)
+
+<!-- END doctoc generated TOC please keep comment here to allow auto update -->
+
+<!-- SPDX-License-Identifier: Apache-2.0
+     https://www.apache.org/licenses/LICENSE-2.0 -->
+
+# spec-validator
+
+**Capability:** capability:setup
+
+Validates spec files in `tools/spec-loop/specs/` — the counterpart to
+`tools/skill-and-tool-validator/` for the spec side of the framework.
+
+## What it checks
+
+For every `.md` file that carries a YAML frontmatter block:
+
+1. **Required frontmatter keys** — `title`, `status`, `kind`, `mode`,
+   `source`, `acceptance`.
+2. **Valid `status`** — `stable` | `experimental` | `proposed` | `off`.
+3. **Valid `kind`** — `feature` | `fix` | `docs` | `chore`.
+4. **Valid `mode`** — `Triage` | `Mentoring` | `Drafting` | `Pairing` | `infra`.
+5. **Non-empty `acceptance` list** — at least one `- item` entry.
+6. **Required body sections** — `## What it does`, `## Where it lives`,
+   `## Behaviour & contract`, `## Out of scope`, `## Acceptance criteria`,
+   `## Validation`.
+7. **Validation section has a fenced code block** — at least one `` ```…``` ``
+   block so build-loop backpressure commands are always explicit.
+
+Files without frontmatter (e.g. `README.md`, `overview.md`) are silently
+skipped — they are index/overview docs, not functional specs.
+
+## Usage
+
+```bash
+# Run against the default spec directory
+uv run --project tools/spec-validator spec-validate
+
+# Run against a specific directory or file
+uv run --project tools/spec-validator spec-validate tools/spec-loop/specs/
+
+# Run the test suite
+uv run --project tools/spec-validator --group dev pytest
+```

tools/spec-validator/pyproject.toml

@@ -0,0 +1,58 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+
+[build-system]
+requires = ["hatchling"]
+build-backend = "hatchling.build"
+
+[project]
+name = "spec-validator"
+version = "0.1.0"
+description = "Validate spec files — YAML frontmatter and required body sections."
+readme = "README.md"
+requires-python = ">=3.11"
+license = { text = "Apache-2.0" }
+dependencies = []
+
+[project.scripts]
+spec-validate = "spec_validator:main"
+
+[dependency-groups]
+dev = [
+  "pytest>=8.0",
+  "ruff>=0.6",
+]
+
+[tool.hatch.build.targets.wheel]
+packages = ["src/spec_validator"]
+
+[tool.ruff]
+line-length = 110
+target-version = "py311"
+src = ["src", "tests"]
+
+[tool.ruff.lint]
+select = ["E", "W", "F", "I", "B", "UP", "SIM", "C4", "RUF"]
+ignore = ["E501"]
+
+[tool.ruff.lint.per-file-ignores]
+"tests/**" = ["B", "SIM"]
+
+[tool.pytest.ini_options]
+minversion = "8.0"
+addopts = "-ra -q"
+testpaths = ["tests"]