diff --git a/README.md b/README.md
index 068ee8384..68a50f1be 100644
--- a/README.md
+++ b/README.md
@@ -41,6 +41,7 @@ trunk check enable {linter}
 | Technology      | Linters                                                                                                                                  |
 | --------------- | ---------------------------------------------------------------------------------------------------------------------------------------- |
 | All             | [codespell], [cspell], [gitleaks], [git-diff-check], [ls-lint], [pre-commit-hooks], [trunk-toolbox], [vale]                              |
+| AI agents       | [lintlang]                                                                                                                               |
 | Ansible         | [ansible-lint]                                                                                                                           |
 | Apex            | [pmd]                                                                                                                                    |
 | Bash            | [shellcheck], [shfmt]                                                                                                                    |
@@ -138,6 +139,7 @@ trunk check enable {linter}
 [isort]: https://github.com/PyCQA/isort#readme
 [ktlint]: https://github.com/pinterest/ktlint#readme
 [kube-linter]: https://github.com/stackrox/kube-linter#readme
+[lintlang]: https://github.com/hermes-labs-ai/lintlang
 [ls-lint]: https://github.com/loeffel-io/ls-lint#readme
 [markdownlint]: https://github.com/DavidAnson/markdownlint#readme
 [markdownlint-cli2]: https://github.com/DavidAnson/markdownlint-cli2#readme
diff --git a/linters/lintlang/lintlang.test.ts b/linters/lintlang/lintlang.test.ts
new file mode 100644
index 000000000..c9c1b0d92
--- /dev/null
+++ b/linters/lintlang/lintlang.test.ts
@@ -0,0 +1,3 @@
+import { linterCheckTest } from "tests";
+
+linterCheckTest({ linterName: "lintlang" });
diff --git a/linters/lintlang/plugin.yaml b/linters/lintlang/plugin.yaml
new file mode 100644
index 000000000..762bbcf3f
--- /dev/null
+++ b/linters/lintlang/plugin.yaml
@@ -0,0 +1,27 @@
+version: 0.1
+tools:
+  definitions:
+    - name: lintlang
+      runtime: python
+      package: lintlang
+      shims: [lintlang]
+      known_good_version: 0.6.0
+lint:
+  definitions:
+    - name: lintlang
+      description:
+        Static analysis for AI agent instructions, tool descriptions, and agent configuration
+      files: [markdown, yaml, json, python]
+      tools: [lintlang]
+      known_good_version: 0.6.0
+      suggest_if: never
+      commands:
+        - name: lint
+          output: sarif
+          run: lintlang scan --format sarif --fail-on fail ${target}
+          success_codes: [0, 1]
+          read_output_from: stdout
+          batch: true
+      version_command:
+        parse_regex: lintlang ${semver}
+        run: lintlang --version
diff --git a/linters/lintlang/test_data/clean.in.yaml b/linters/lintlang/test_data/clean.in.yaml
new file mode 100644
index 000000000..ea321afe4
--- /dev/null
+++ b/linters/lintlang/test_data/clean.in.yaml
@@ -0,0 +1,16 @@
+system_prompt: |
+  You are a weather information assistant.
+  Stop and report the failure after one retry.
+tools:
+  - name: get_current_weather
+    description: Retrieve current weather for one named location. Do not use this tool for forecasts.
+    parameters:
+      type: object
+      properties:
+        location:
+          type: string
+          description: City and country for the requested weather.
+      required: [location]
+constraints:
+  max_iterations: 2
+  timeout_seconds: 30
diff --git a/linters/lintlang/test_data/findings.in.yaml b/linters/lintlang/test_data/findings.in.yaml
new file mode 100644
index 000000000..5afb8f24a
--- /dev/null
+++ b/linters/lintlang/test_data/findings.in.yaml
@@ -0,0 +1,10 @@
+system_prompt: |
+  You are a customer support agent. Help the user with their issues.
+tools:
+  - name: process_ticket
+    description: ""
+    parameters:
+      type: object
+      properties:
+        ticket_id:
+          type: string
diff --git a/linters/lintlang/test_data/lintlang_v0.6.0_clean.check.shot b/linters/lintlang/test_data/lintlang_v0.6.0_clean.check.shot
new file mode 100644
index 000000000..4e97e436f
--- /dev/null
+++ b/linters/lintlang/test_data/lintlang_v0.6.0_clean.check.shot
@@ -0,0 +1,30 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`Testing linter lintlang test clean 1`] = `
+{
+  "issues": [],
+  "lintActions": [
+    {
+      "command": "lint",
+      "fileGroupName": "yaml",
+      "linter": "lintlang",
+      "paths": [
+        "test_data/clean.in.yaml",
+      ],
+      "verb": "TRUNK_VERB_CHECK",
+    },
+    {
+      "command": "lint",
+      "fileGroupName": "yaml",
+      "linter": "lintlang",
+      "paths": [
+        "test_data/clean.in.yaml",
+      ],
+      "upstream": true,
+      "verb": "TRUNK_VERB_CHECK",
+    },
+  ],
+  "taskFailures": [],
+  "unformattedFiles": [],
+}
+`;
diff --git a/linters/lintlang/test_data/lintlang_v0.6.0_findings.check.shot b/linters/lintlang/test_data/lintlang_v0.6.0_findings.check.shot
new file mode 100644
index 000000000..293c36584
--- /dev/null
+++ b/linters/lintlang/test_data/lintlang_v0.6.0_findings.check.shot
@@ -0,0 +1,64 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`Testing linter lintlang test findings 1`] = `
+{
+  "issues": [
+    {
+      "code": "H1.1",
+      "column": "1",
+      "file": "test_data/findings.in.yaml",
+      "issueClass": "ISSUE_CLASS_NEW",
+      "level": "LEVEL_HIGH",
+      "line": "1",
+      "linter": "lintlang",
+      "message": "Tool 'process_ticket' has no description. Suggested action: Add a specific, disambiguating description that explains WHEN to use this tool, not just WHAT it does.",
+      "targetType": "yaml",
+    },
+    {
+      "code": "H2",
+      "column": "1",
+      "file": "test_data/findings.in.yaml",
+      "issueClass": "ISSUE_CLASS_NEW",
+      "level": "LEVEL_HIGH",
+      "line": "1",
+      "linter": "lintlang",
+      "message": "System prompt defines tools but contains no termination conditions, retry budgets, or progress checks. Suggested action: Add explicit constraints: 'You have a maximum of 5 tool calls per task. If no progress after 2 attempts, stop and report the issue.'",
+      "targetType": "yaml",
+    },
+    {
+      "code": "H3",
+      "column": "1",
+      "file": "test_data/findings.in.yaml",
+      "issueClass": "ISSUE_CLASS_NEW",
+      "level": "LEVEL_MEDIUM",
+      "line": "1",
+      "linter": "lintlang",
+      "message": "Parameter 'ticket_id' in tool 'process_ticket' has no description. Suggested action: Add a description explaining what this parameter means semantically, not just its type.",
+      "targetType": "yaml",
+    },
+  ],
+  "lintActions": [
+    {
+      "command": "lint",
+      "fileGroupName": "yaml",
+      "linter": "lintlang",
+      "paths": [
+        "test_data/findings.in.yaml",
+      ],
+      "verb": "TRUNK_VERB_CHECK",
+    },
+    {
+      "command": "lint",
+      "fileGroupName": "yaml",
+      "linter": "lintlang",
+      "paths": [
+        "test_data/findings.in.yaml",
+      ],
+      "upstream": true,
+      "verb": "TRUNK_VERB_CHECK",
+    },
+  ],
+  "taskFailures": [],
+  "unformattedFiles": [],
+}
+`;