From 9b4017a95feb5e66a95f0dca6c5379bd2e5018a8 Mon Sep 17 00:00:00 2001
From: Anton Gulin <i@anton.qa>
Date: Sun, 5 Jul 2026 16:08:57 -0700
Subject: [PATCH 1/6] fix(validate): reject unquoted frontmatter values
 containing ': '
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Reworks #30 without the yaml dependency (which broke the bundled dist
with a CJS interop error). The hand-rolled frontmatter parser now flags
top-level unquoted values containing ': ' — invalid YAML that the
opencode runtime parser silently drops — with the offending key, line
number, and a quoting hint. Quoted values, block scalars, continuation
lines, and list items are unaffected.

Co-authored-by: Michael Ledin <mledin89@gmail.com>
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
---
 plugin/dist/build-manifest.json |  4 +-
 plugin/dist/skill-creator.js    | 21 +++++--
 plugin/lib/validate.ts          | 23 +++++++-
 plugin/test/validate.test.ts    | 99 +++++++++++++++++++++++++++++++++
 4 files changed, 139 insertions(+), 8 deletions(-)
 create mode 100644 plugin/test/validate.test.ts

diff --git a/plugin/dist/build-manifest.json b/plugin/dist/build-manifest.json
index 0ed93ca..8fb2059 100644
--- a/plugin/dist/build-manifest.json
+++ b/plugin/dist/build-manifest.json
@@ -1,6 +1,6 @@
 {
   "entrypoint": "skill-creator.ts",
   "runtimeEntrypoint": "runtime-entry.ts",
-  "sourceHash": "6e4c1da97ef75f263cacd5f8e706bd849c99792b84a7a505148fa234de660aaf",
-  "builtAt": "2026-06-23T08:01:15.963Z"
+  "sourceHash": "64e8c9dc7347521f3d3c0a3cb4f308cb12cd50ba0c9c1277faad723a6ef44e0d",
+  "builtAt": "2026-07-05T23:08:30.744Z"
 }
diff --git a/plugin/dist/skill-creator.js b/plugin/dist/skill-creator.js
index 12febec..e9a41f1 100644
--- a/plugin/dist/skill-creator.js
+++ b/plugin/dist/skill-creator.js
@@ -10746,7 +10746,7 @@ class JSONSchemaGenerator {
               if (val === undefined) {
                 if (this.unrepresentable === "throw") {
                   throw new Error("Literal `undefined` cannot be represented in JSON Schema");
-                } else {}
+                }
               } else if (typeof val === "bigint") {
                 if (this.unrepresentable === "throw") {
                   throw new Error("BigInt literals cannot be represented in JSON Schema");
@@ -12352,6 +12352,12 @@ var ALLOWED_PROPERTIES = new Set([
   "metadata",
   "compatibility"
 ]);
+function isQuotedValue(value) {
+  return value.startsWith('"') && value.endsWith('"') || value.startsWith("'") && value.endsWith("'");
+}
+function isBlockScalarMarker(value) {
+  return /^[|>][+-]?$/.test(value);
+}
 function validateSkill(skillPath) {
   const skillMdPath = join(skillPath, "SKILL.md");
   if (!existsSync(skillMdPath)) {
@@ -12370,8 +12376,9 @@ function validateSkill(skillPath) {
   let currentKey = "";
   let currentValue = "";
   let inMultiline = false;
-  for (const line of frontmatterText.split(`
-`)) {
+  const frontmatterLines = frontmatterText.split(`
+`);
+  for (const [index, line] of frontmatterLines.entries()) {
     if (inMultiline) {
       if (line.startsWith("  ") || line.startsWith("\t")) {
         currentValue += " " + line.trim();
@@ -12385,7 +12392,13 @@ function validateSkill(skillPath) {
     if (kvMatch) {
       currentKey = kvMatch[1];
       const value = kvMatch[2].trim();
-      if ([">", "|", ">-", "|-"].includes(value)) {
+      if (value && !isQuotedValue(value) && !isBlockScalarMarker(value) && value.includes(": ")) {
+        return {
+          valid: false,
+          message: `Invalid frontmatter value for '${currentKey}' on line ${index + 1}: unquoted values containing ': ' are invalid YAML and the runtime will drop this skill. Hint: quote the value (e.g. ${currentKey}: "your text here").`
+        };
+      }
+      if (isBlockScalarMarker(value)) {
         currentValue = "";
         inMultiline = true;
       } else if (currentKey === "metadata" && (value === "" || value === "{}")) {
diff --git a/plugin/lib/validate.ts b/plugin/lib/validate.ts
index afa9f1f..b085a97 100644
--- a/plugin/lib/validate.ts
+++ b/plugin/lib/validate.ts
@@ -23,6 +23,17 @@ const ALLOWED_PROPERTIES = new Set([
   "compatibility",
 ])
 
+function isQuotedValue(value: string): boolean {
+  return (
+    (value.startsWith('"') && value.endsWith('"')) ||
+    (value.startsWith("'") && value.endsWith("'"))
+  )
+}
+
+function isBlockScalarMarker(value: string): boolean {
+  return /^[|>][+-]?$/.test(value)
+}
+
 /**
  * Validate a skill directory.
  *
@@ -56,7 +67,8 @@ export function validateSkill(skillPath: string): ValidationResult {
   let currentValue = ""
   let inMultiline = false
 
-  for (const line of frontmatterText.split("\n")) {
+  const frontmatterLines = frontmatterText.split("\n")
+  for (const [index, line] of frontmatterLines.entries()) {
     if (inMultiline) {
       if (line.startsWith("  ") || line.startsWith("\t")) {
         currentValue += " " + line.trim()
@@ -72,7 +84,14 @@ export function validateSkill(skillPath: string): ValidationResult {
       currentKey = kvMatch[1]
       const value = kvMatch[2].trim()
 
-      if ([">", "|", ">-", "|-"].includes(value)) {
+      if (value && !isQuotedValue(value) && !isBlockScalarMarker(value) && value.includes(": ")) {
+        return {
+          valid: false,
+          message: `Invalid frontmatter value for '${currentKey}' on line ${index + 1}: unquoted values containing ': ' are invalid YAML and the runtime will drop this skill. Hint: quote the value (e.g. ${currentKey}: "your text here").`,
+        }
+      }
+
+      if (isBlockScalarMarker(value)) {
         currentValue = ""
         inMultiline = true
       } else if (
diff --git a/plugin/test/validate.test.ts b/plugin/test/validate.test.ts
new file mode 100644
index 0000000..b13ebfc
--- /dev/null
+++ b/plugin/test/validate.test.ts
@@ -0,0 +1,99 @@
+import { mkdirSync, mkdtempSync, rmSync, writeFileSync } from "fs"
+import { tmpdir } from "os"
+import { join } from "path"
+
+import { expect, test } from "bun:test"
+
+import { validateSkill } from "../lib/validate"
+
+const withSkill = <T>(frontmatter: string, fn: (skillPath: string) => T): T => {
+  const dir = mkdtempSync(join(tmpdir(), "skill-creator-validate-"))
+  try {
+    mkdirSync(dir, { recursive: true })
+    writeFileSync(join(dir, "SKILL.md"), `---\n${frontmatter}\n---\n\n# Test Skill\n`)
+    return fn(dir)
+  } finally {
+    rmSync(dir, { recursive: true, force: true })
+  }
+}
+
+test("quoted description containing colon-space passes", () => {
+  withSkill(
+    `name: pdf-reader
+description: "Use for PDF files: reading, extracting."`,
+    (skillPath) => {
+      expect(validateSkill(skillPath)).toEqual({
+        valid: true,
+        message: "Skill is valid!",
+      })
+    },
+  )
+})
+
+test("unquoted description without colon-space passes", () => {
+  withSkill(
+    `name: pdf-reader
+description: Use for PDF files, reading and extracting.`,
+    (skillPath) => {
+      expect(validateSkill(skillPath)).toEqual({
+        valid: true,
+        message: "Skill is valid!",
+      })
+    },
+  )
+})
+
+test("bundled skill fixture passes validation", () => {
+  expect(validateSkill(join(import.meta.dir, "..", "skill"))).toEqual({
+    valid: true,
+    message: "Skill is valid!",
+  })
+})
+
+test("unquoted description with colon-space fails with quote hint", () => {
+  withSkill(
+    `name: pdf-reader
+description: Use for PDF files: reading, extracting.`,
+    (skillPath) => {
+      const result = validateSkill(skillPath)
+
+      expect(result.valid).toBe(false)
+      expect(result.message).toContain("description")
+      expect(result.message).toContain("line 2")
+      expect(result.message).toContain("Hint: quote the value")
+      expect(result.message).toContain("description: \"your text here\"")
+      expect(result.message).toContain("unquoted values containing ': ' are invalid YAML")
+      expect(result.message).toContain("runtime will drop this skill")
+    },
+  )
+})
+
+test("unquoted value with colon-space mid-value fails", () => {
+  withSkill(
+    `name: pdf-reader
+description: Use when reading docs.
+compatibility: Works with docs: markdown and PDF`,
+    (skillPath) => {
+      const result = validateSkill(skillPath)
+
+      expect(result.valid).toBe(false)
+      expect(result.message).toContain("compatibility")
+      expect(result.message).toContain("line 3")
+    },
+  )
+})
+
+test("unquoted name with colon-space fails before name validation", () => {
+  withSkill(
+    `name: pdf: reader
+description: Use when reading docs.`,
+    (skillPath) => {
+      const result = validateSkill(skillPath)
+
+      expect(result.valid).toBe(false)
+      expect(result.message).toContain("name")
+      expect(result.message).toContain("line 1")
+      expect(result.message).toContain("Hint: quote the value")
+    },
+  )
+})

From a5b69fff7ef9d290a3283b746d6a85d853770a7f Mon Sep 17 00:00:00 2001
From: Anton Gulin <i@anton.qa>
Date: Sun, 5 Jul 2026 16:14:36 -0700
Subject: [PATCH 2/6] fix(pr-feedback): guard single-char quoted values, add
 block-scalar and single-quote tests

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
---
 plugin/dist/build-manifest.json |  4 ++--
 plugin/dist/skill-creator.js    |  2 +-
 plugin/lib/validate.ts          |  5 +++--
 plugin/test/validate.test.ts    | 27 +++++++++++++++++++++++++++
 4 files changed, 33 insertions(+), 5 deletions(-)

diff --git a/plugin/dist/build-manifest.json b/plugin/dist/build-manifest.json
index 8fb2059..7a579ac 100644
--- a/plugin/dist/build-manifest.json
+++ b/plugin/dist/build-manifest.json
@@ -1,6 +1,6 @@
 {
   "entrypoint": "skill-creator.ts",
   "runtimeEntrypoint": "runtime-entry.ts",
-  "sourceHash": "64e8c9dc7347521f3d3c0a3cb4f308cb12cd50ba0c9c1277faad723a6ef44e0d",
-  "builtAt": "2026-07-05T23:08:30.744Z"
+  "sourceHash": "720df910610651e9a5e1366d35e69b1676ebde2eaadb3a6428edd43112a878a0",
+  "builtAt": "2026-07-05T23:14:25.765Z"
 }
diff --git a/plugin/dist/skill-creator.js b/plugin/dist/skill-creator.js
index e9a41f1..a769fc7 100644
--- a/plugin/dist/skill-creator.js
+++ b/plugin/dist/skill-creator.js
@@ -12353,7 +12353,7 @@ var ALLOWED_PROPERTIES = new Set([
   "compatibility"
 ]);
 function isQuotedValue(value) {
-  return value.startsWith('"') && value.endsWith('"') || value.startsWith("'") && value.endsWith("'");
+  return value.length >= 2 && (value.startsWith('"') && value.endsWith('"') || value.startsWith("'") && value.endsWith("'"));
 }
 function isBlockScalarMarker(value) {
   return /^[|>][+-]?$/.test(value);
diff --git a/plugin/lib/validate.ts b/plugin/lib/validate.ts
index b085a97..a19ca3b 100644
--- a/plugin/lib/validate.ts
+++ b/plugin/lib/validate.ts
@@ -25,8 +25,9 @@ const ALLOWED_PROPERTIES = new Set([
 
 function isQuotedValue(value: string): boolean {
   return (
-    (value.startsWith('"') && value.endsWith('"')) ||
-    (value.startsWith("'") && value.endsWith("'"))
+    value.length >= 2 &&
+    ((value.startsWith('"') && value.endsWith('"')) ||
+      (value.startsWith("'") && value.endsWith("'")))
   )
 }
 
diff --git a/plugin/test/validate.test.ts b/plugin/test/validate.test.ts
index b13ebfc..e8c344f 100644
--- a/plugin/test/validate.test.ts
+++ b/plugin/test/validate.test.ts
@@ -68,6 +68,33 @@ description: Use for PDF files: reading, extracting.`,
   )
 })
 
+test("single-quoted description containing colon-space passes", () => {
+  withSkill(
+    `name: pdf-reader
+description: 'Use for PDF files: reading, extracting.'`,
+    (skillPath) => {
+      expect(validateSkill(skillPath)).toEqual({
+        valid: true,
+        message: "Skill is valid!",
+      })
+    },
+  )
+})
+
+test("block scalar content with colon-space passes", () => {
+  withSkill(
+    `name: pdf-reader
+description: |
+  Use for PDF files: reading, extracting.`,
+    (skillPath) => {
+      expect(validateSkill(skillPath)).toEqual({
+        valid: true,
+        message: "Skill is valid!",
+      })
+    },
+  )
+})
+
 test("unquoted value with colon-space mid-value fails", () => {
   withSkill(
     `name: pdf-reader

From 3e39568a7166b65c08ab21abfc539aa6fe7fe26e Mon Sep 17 00:00:00 2001
From: Anton Gulin <i@anton.qa>
Date: Sun, 5 Jul 2026 16:18:04 -0700
Subject: [PATCH 3/6] fix(pr-feedback): support block scalar indentation
 indicators in marker regex

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
---
 plugin/dist/build-manifest.json | 4 ++--
 plugin/dist/skill-creator.js    | 2 +-
 plugin/lib/validate.ts          | 3 ++-
 plugin/test/validate.test.ts    | 2 +-
 4 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/plugin/dist/build-manifest.json b/plugin/dist/build-manifest.json
index 7a579ac..b0bf0c1 100644
--- a/plugin/dist/build-manifest.json
+++ b/plugin/dist/build-manifest.json
@@ -1,6 +1,6 @@
 {
   "entrypoint": "skill-creator.ts",
   "runtimeEntrypoint": "runtime-entry.ts",
-  "sourceHash": "720df910610651e9a5e1366d35e69b1676ebde2eaadb3a6428edd43112a878a0",
-  "builtAt": "2026-07-05T23:14:25.765Z"
+  "sourceHash": "17ed10f1d559d55448d0af96c5fc2f4d70a3a2c67bdf5840d1b8b272da85a4a6",
+  "builtAt": "2026-07-05T23:17:49.191Z"
 }
diff --git a/plugin/dist/skill-creator.js b/plugin/dist/skill-creator.js
index a769fc7..a2f2ffb 100644
--- a/plugin/dist/skill-creator.js
+++ b/plugin/dist/skill-creator.js
@@ -12356,7 +12356,7 @@ function isQuotedValue(value) {
   return value.length >= 2 && (value.startsWith('"') && value.endsWith('"') || value.startsWith("'") && value.endsWith("'"));
 }
 function isBlockScalarMarker(value) {
-  return /^[|>][+-]?$/.test(value);
+  return /^[|>](?:[1-9][+-]?|[+-][1-9]?)?$/.test(value);
 }
 function validateSkill(skillPath) {
   const skillMdPath = join(skillPath, "SKILL.md");
diff --git a/plugin/lib/validate.ts b/plugin/lib/validate.ts
index a19ca3b..b4d1008 100644
--- a/plugin/lib/validate.ts
+++ b/plugin/lib/validate.ts
@@ -32,7 +32,8 @@ function isQuotedValue(value: string): boolean {
 }
 
 function isBlockScalarMarker(value: string): boolean {
-  return /^[|>][+-]?$/.test(value)
+  // header allows indentation (1-9) and chomping (+/-) indicators in either order
+  return /^[|>](?:[1-9][+-]?|[+-][1-9]?)?$/.test(value)
 }
 
 /**
diff --git a/plugin/test/validate.test.ts b/plugin/test/validate.test.ts
index e8c344f..86f042b 100644
--- a/plugin/test/validate.test.ts
+++ b/plugin/test/validate.test.ts
@@ -84,7 +84,7 @@ description: 'Use for PDF files: reading, extracting.'`,
 test("block scalar content with colon-space passes", () => {
   withSkill(
     `name: pdf-reader
-description: |
+description: |2-
   Use for PDF files: reading, extracting.`,
     (skillPath) => {
       expect(validateSkill(skillPath)).toEqual({

From 2e22bec30bee815f3fb0c9a36f7905a6b46f0696 Mon Sep 17 00:00:00 2001
From: Anton Gulin <i@anton.qa>
Date: Sun, 5 Jul 2026 16:21:03 -0700
Subject: [PATCH 4/6] fix(pr-feedback): also reject unquoted values ending with
 ':'

Verified against a strict YAML parser: 'description: Note:' is a parse
error the runtime drops, same as mid-value ': '.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
---
 plugin/dist/build-manifest.json |  4 ++--
 plugin/dist/skill-creator.js    |  4 ++--
 plugin/lib/validate.ts          |  9 +++++++--
 plugin/test/validate.test.ts    | 32 +++++++++++++++++++++++++++++++-
 4 files changed, 42 insertions(+), 7 deletions(-)

diff --git a/plugin/dist/build-manifest.json b/plugin/dist/build-manifest.json
index b0bf0c1..c52c202 100644
--- a/plugin/dist/build-manifest.json
+++ b/plugin/dist/build-manifest.json
@@ -1,6 +1,6 @@
 {
   "entrypoint": "skill-creator.ts",
   "runtimeEntrypoint": "runtime-entry.ts",
-  "sourceHash": "17ed10f1d559d55448d0af96c5fc2f4d70a3a2c67bdf5840d1b8b272da85a4a6",
-  "builtAt": "2026-07-05T23:17:49.191Z"
+  "sourceHash": "3c1b635dd079afaa73cd244d2ed41c5ea7f546981bc35b7750c23c27d71144bd",
+  "builtAt": "2026-07-05T23:20:53.528Z"
 }
diff --git a/plugin/dist/skill-creator.js b/plugin/dist/skill-creator.js
index a2f2ffb..fbc3852 100644
--- a/plugin/dist/skill-creator.js
+++ b/plugin/dist/skill-creator.js
@@ -12392,10 +12392,10 @@ function validateSkill(skillPath) {
     if (kvMatch) {
       currentKey = kvMatch[1];
       const value = kvMatch[2].trim();
-      if (value && !isQuotedValue(value) && !isBlockScalarMarker(value) && value.includes(": ")) {
+      if (value && !isQuotedValue(value) && !isBlockScalarMarker(value) && (value.includes(": ") || value.endsWith(":"))) {
         return {
           valid: false,
-          message: `Invalid frontmatter value for '${currentKey}' on line ${index + 1}: unquoted values containing ': ' are invalid YAML and the runtime will drop this skill. Hint: quote the value (e.g. ${currentKey}: "your text here").`
+          message: `Invalid frontmatter value for '${currentKey}' on line ${index + 1}: unquoted values containing ': ' or ending with ':' are invalid YAML and the runtime will drop this skill. Hint: quote the value (e.g. ${currentKey}: "your text here").`
         };
       }
       if (isBlockScalarMarker(value)) {
diff --git a/plugin/lib/validate.ts b/plugin/lib/validate.ts
index b4d1008..78e8863 100644
--- a/plugin/lib/validate.ts
+++ b/plugin/lib/validate.ts
@@ -86,10 +86,15 @@ export function validateSkill(skillPath: string): ValidationResult {
       currentKey = kvMatch[1]
       const value = kvMatch[2].trim()
 
-      if (value && !isQuotedValue(value) && !isBlockScalarMarker(value) && value.includes(": ")) {
+      if (
+        value &&
+        !isQuotedValue(value) &&
+        !isBlockScalarMarker(value) &&
+        (value.includes(": ") || value.endsWith(":"))
+      ) {
         return {
           valid: false,
-          message: `Invalid frontmatter value for '${currentKey}' on line ${index + 1}: unquoted values containing ': ' are invalid YAML and the runtime will drop this skill. Hint: quote the value (e.g. ${currentKey}: "your text here").`,
+          message: `Invalid frontmatter value for '${currentKey}' on line ${index + 1}: unquoted values containing ': ' or ending with ':' are invalid YAML and the runtime will drop this skill. Hint: quote the value (e.g. ${currentKey}: "your text here").`,
         }
       }
 
diff --git a/plugin/test/validate.test.ts b/plugin/test/validate.test.ts
index 86f042b..f76ffc2 100644
--- a/plugin/test/validate.test.ts
+++ b/plugin/test/validate.test.ts
@@ -62,7 +62,9 @@ description: Use for PDF files: reading, extracting.`,
       expect(result.message).toContain("line 2")
       expect(result.message).toContain("Hint: quote the value")
       expect(result.message).toContain("description: \"your text here\"")
-      expect(result.message).toContain("unquoted values containing ': ' are invalid YAML")
+      expect(result.message).toContain(
+        "unquoted values containing ': ' or ending with ':' are invalid YAML",
+      )
       expect(result.message).toContain("runtime will drop this skill")
     },
   )
@@ -110,6 +112,34 @@ compatibility: Works with docs: markdown and PDF`,
   )
 })
 
+test("unquoted value ending with colon fails", () => {
+  withSkill(
+    `name: pdf-reader
+description: Note:`,
+    (skillPath) => {
+      const result = validateSkill(skillPath)
+
+      expect(result.valid).toBe(false)
+      expect(result.message).toContain("description")
+      expect(result.message).toContain("line 2")
+      expect(result.message).toContain("Hint: quote the value")
+    },
+  )
+})
+
+test("unquoted value ending with colon-space fails", () => {
+  withSkill(
+    `name: pdf-reader
+description: Note: `,
+    (skillPath) => {
+      const result = validateSkill(skillPath)
+
+      expect(result.valid).toBe(false)
+      expect(result.message).toContain("description")
+    },
+  )
+})
+
 test("unquoted name with colon-space fails before name validation", () => {
   withSkill(
     `name: pdf: reader

From 7638c4d868d40930d1a590158924d740153dcab2 Mon Sep 17 00:00:00 2001
From: Anton Gulin <i@anton.qa>
Date: Sun, 5 Jul 2026 16:23:03 -0700
Subject: [PATCH 5/6] fix(pr-feedback): treat colon-tab as mapping separator;
 tighten test assertions

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
---
 plugin/dist/build-manifest.json |  4 ++--
 plugin/dist/skill-creator.js    |  2 +-
 plugin/lib/validate.ts          |  2 +-
 plugin/test/validate.test.ts    | 16 ++++++++++++++++
 4 files changed, 20 insertions(+), 4 deletions(-)

diff --git a/plugin/dist/build-manifest.json b/plugin/dist/build-manifest.json
index c52c202..ab83e14 100644
--- a/plugin/dist/build-manifest.json
+++ b/plugin/dist/build-manifest.json
@@ -1,6 +1,6 @@
 {
   "entrypoint": "skill-creator.ts",
   "runtimeEntrypoint": "runtime-entry.ts",
-  "sourceHash": "3c1b635dd079afaa73cd244d2ed41c5ea7f546981bc35b7750c23c27d71144bd",
-  "builtAt": "2026-07-05T23:20:53.528Z"
+  "sourceHash": "71d880c57ec805e651487291b5c4d0a78730e47ac2a1d1e56a99b61096c4cafe",
+  "builtAt": "2026-07-05T23:23:01.829Z"
 }
diff --git a/plugin/dist/skill-creator.js b/plugin/dist/skill-creator.js
index fbc3852..11a1731 100644
--- a/plugin/dist/skill-creator.js
+++ b/plugin/dist/skill-creator.js
@@ -12392,7 +12392,7 @@ function validateSkill(skillPath) {
     if (kvMatch) {
       currentKey = kvMatch[1];
       const value = kvMatch[2].trim();
-      if (value && !isQuotedValue(value) && !isBlockScalarMarker(value) && (value.includes(": ") || value.endsWith(":"))) {
+      if (value && !isQuotedValue(value) && !isBlockScalarMarker(value) && (/:[ \t]/.test(value) || value.endsWith(":"))) {
         return {
           valid: false,
           message: `Invalid frontmatter value for '${currentKey}' on line ${index + 1}: unquoted values containing ': ' or ending with ':' are invalid YAML and the runtime will drop this skill. Hint: quote the value (e.g. ${currentKey}: "your text here").`
diff --git a/plugin/lib/validate.ts b/plugin/lib/validate.ts
index 78e8863..94f9233 100644
--- a/plugin/lib/validate.ts
+++ b/plugin/lib/validate.ts
@@ -90,7 +90,7 @@ export function validateSkill(skillPath: string): ValidationResult {
         value &&
         !isQuotedValue(value) &&
         !isBlockScalarMarker(value) &&
-        (value.includes(": ") || value.endsWith(":"))
+        (/:[ \t]/.test(value) || value.endsWith(":"))
       ) {
         return {
           valid: false,
diff --git a/plugin/test/validate.test.ts b/plugin/test/validate.test.ts
index f76ffc2..80ace55 100644
--- a/plugin/test/validate.test.ts
+++ b/plugin/test/validate.test.ts
@@ -136,6 +136,22 @@ description: Note: `,
 
       expect(result.valid).toBe(false)
       expect(result.message).toContain("description")
+      expect(result.message).toContain("line 2")
+      expect(result.message).toContain("Hint: quote the value")
+    },
+  )
+})
+
+test("unquoted value with colon-tab fails", () => {
+  withSkill(
+    `name: pdf-reader
+description: Use for PDF files:\treading`,
+    (skillPath) => {
+      const result = validateSkill(skillPath)
+
+      expect(result.valid).toBe(false)
+      expect(result.message).toContain("description")
+      expect(result.message).toContain("line 2")
     },
   )
 })

From 9c2c9696cbb31e4ff3f8d7f0aaf3278f7293d441 Mon Sep 17 00:00:00 2001
From: Anton Gulin <i@anton.qa>
Date: Sun, 5 Jul 2026 16:25:47 -0700
Subject: [PATCH 6/6] fix(pr-feedback): report file line numbers (not
 frontmatter-relative), document heuristic

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
---
 plugin/dist/build-manifest.json |  4 ++--
 plugin/dist/skill-creator.js    |  2 +-
 plugin/lib/validate.ts          |  5 ++++-
 plugin/test/validate.test.ts    | 14 +++++++-------
 4 files changed, 14 insertions(+), 11 deletions(-)

diff --git a/plugin/dist/build-manifest.json b/plugin/dist/build-manifest.json
index ab83e14..8a56679 100644
--- a/plugin/dist/build-manifest.json
+++ b/plugin/dist/build-manifest.json
@@ -1,6 +1,6 @@
 {
   "entrypoint": "skill-creator.ts",
   "runtimeEntrypoint": "runtime-entry.ts",
-  "sourceHash": "71d880c57ec805e651487291b5c4d0a78730e47ac2a1d1e56a99b61096c4cafe",
-  "builtAt": "2026-07-05T23:23:01.829Z"
+  "sourceHash": "a95606cc6b846614df711940b5cae746a9ef7e2b27521082bd454fb2f8831ada",
+  "builtAt": "2026-07-05T23:25:34.085Z"
 }
diff --git a/plugin/dist/skill-creator.js b/plugin/dist/skill-creator.js
index 11a1731..416e5c3 100644
--- a/plugin/dist/skill-creator.js
+++ b/plugin/dist/skill-creator.js
@@ -12395,7 +12395,7 @@ function validateSkill(skillPath) {
       if (value && !isQuotedValue(value) && !isBlockScalarMarker(value) && (/:[ \t]/.test(value) || value.endsWith(":"))) {
         return {
           valid: false,
-          message: `Invalid frontmatter value for '${currentKey}' on line ${index + 1}: unquoted values containing ': ' or ending with ':' are invalid YAML and the runtime will drop this skill. Hint: quote the value (e.g. ${currentKey}: "your text here").`
+          message: `Invalid frontmatter value for '${currentKey}' on line ${index + 2}: unquoted values containing ': ' or ending with ':' are invalid YAML and the runtime will drop this skill. Hint: quote the value (e.g. ${currentKey}: "your text here").`
         };
       }
       if (isBlockScalarMarker(value)) {
diff --git a/plugin/lib/validate.ts b/plugin/lib/validate.ts
index 94f9233..c703919 100644
--- a/plugin/lib/validate.ts
+++ b/plugin/lib/validate.ts
@@ -23,6 +23,8 @@ const ALLOWED_PROPERTIES = new Set([
   "compatibility",
 ])
 
+// Intentionally simple first/last-char check — this validator is a lint
+// heuristic for common frontmatter mistakes, not a full YAML parser.
 function isQuotedValue(value: string): boolean {
   return (
     value.length >= 2 &&
@@ -94,7 +96,8 @@ export function validateSkill(skillPath: string): ValidationResult {
       ) {
         return {
           valid: false,
-          message: `Invalid frontmatter value for '${currentKey}' on line ${index + 1}: unquoted values containing ': ' or ending with ':' are invalid YAML and the runtime will drop this skill. Hint: quote the value (e.g. ${currentKey}: "your text here").`,
+          // +2: frontmatter starts on file line 2, after the opening ---
+          message: `Invalid frontmatter value for '${currentKey}' on line ${index + 2}: unquoted values containing ': ' or ending with ':' are invalid YAML and the runtime will drop this skill. Hint: quote the value (e.g. ${currentKey}: "your text here").`,
         }
       }
 
diff --git a/plugin/test/validate.test.ts b/plugin/test/validate.test.ts
index 80ace55..74ef73f 100644
--- a/plugin/test/validate.test.ts
+++ b/plugin/test/validate.test.ts
@@ -59,7 +59,7 @@ description: Use for PDF files: reading, extracting.`,
 
       expect(result.valid).toBe(false)
       expect(result.message).toContain("description")
-      expect(result.message).toContain("line 2")
+      expect(result.message).toContain("line 3")
       expect(result.message).toContain("Hint: quote the value")
       expect(result.message).toContain("description: \"your text here\"")
       expect(result.message).toContain(
@@ -107,7 +107,7 @@ compatibility: Works with docs: markdown and PDF`,
 
       expect(result.valid).toBe(false)
       expect(result.message).toContain("compatibility")
-      expect(result.message).toContain("line 3")
+      expect(result.message).toContain("line 4")
     },
   )
 })
@@ -121,13 +121,13 @@ description: Note:`,
 
       expect(result.valid).toBe(false)
       expect(result.message).toContain("description")
-      expect(result.message).toContain("line 2")
+      expect(result.message).toContain("line 3")
       expect(result.message).toContain("Hint: quote the value")
     },
   )
 })
 
-test("unquoted value ending with colon-space fails", () => {
+test("unquoted value with trailing colon-space fails after trim (ends-with-colon path)", () => {
   withSkill(
     `name: pdf-reader
 description: Note: `,
@@ -136,7 +136,7 @@ description: Note: `,
 
       expect(result.valid).toBe(false)
       expect(result.message).toContain("description")
-      expect(result.message).toContain("line 2")
+      expect(result.message).toContain("line 3")
       expect(result.message).toContain("Hint: quote the value")
     },
   )
@@ -151,7 +151,7 @@ description: Use for PDF files:\treading`,
 
       expect(result.valid).toBe(false)
       expect(result.message).toContain("description")
-      expect(result.message).toContain("line 2")
+      expect(result.message).toContain("line 3")
     },
   )
 })
@@ -165,7 +165,7 @@ description: Use when reading docs.`,
 
       expect(result.valid).toBe(false)
       expect(result.message).toContain("name")
-      expect(result.message).toContain("line 1")
+      expect(result.message).toContain("line 2")
       expect(result.message).toContain("Hint: quote the value")
     },
   )