web_fetch fix

kernel/bin/agent

@@ -1670,20 +1670,37 @@ async function bareAgentCompleteOnce(opts) {
  * @returns {string}
  */
 function bareWebFmtErr(e) {
-  if (e == null) return '(null)'
+  if (e === undefined)
+    return 'promise_rejected_with_undefined (no rejection reason)'
+  if (e === null) return 'promise_rejected_with_null'
   if (typeof e === 'string') return e
   if (typeof e !== 'object') return String(e)
   const o = /** @type {Record<string, unknown>} */ (e)
   const msg = o.message
-  if (typeof msg === 'string' && msg.trim()) return msg
-  if (typeof msg === 'number' || typeof msg === 'boolean') return String(msg)
+  if (typeof msg === 'string' && msg.trim()) return bareWebFmtErrAugment(o, msg.trim())
+  if (typeof msg === 'number' || typeof msg === 'boolean')
+    return bareWebFmtErrAugment(o, String(msg))
   const nm = o.name
   const code = o.code
+  const errno = o.errno
   /** @type {string[]} */
   const bits = []
   if (typeof nm === 'string' && nm.trim()) bits.push(nm)
   if (code !== undefined && code !== null && String(code) !== '')
     bits.push('code=' + String(code))
+  if (errno !== undefined && errno !== null && String(errno) !== '')
+    bits.push('errno=' + String(errno))
+  const cause = o.cause
+  if (cause !== undefined && cause !== null && cause !== e) {
+    const cs = bareWebFmtErr(cause)
+    if (cs && cs !== 'unknown_error') bits.push('cause=(' + cs.slice(0, 280) + ')')
+  }
+  const errs = o.errors
+  if (Array.isArray(errs) && errs.length) {
+    errs.slice(0, 5).forEach((sub, i) => {
+      bits.push('agg' + i + '=' + bareWebFmtErr(sub).slice(0, 120))
+    })
+  }
   if (bits.length) return bits.join(' ')
   try {
     const j = JSON.stringify(o)
@@ -1702,6 +1719,29 @@ function bareWebFmtErr(e) {
   return 'unknown_error'
 }
 
+/**
+ * Append errno/syscall from Node-ish errors when message alone is vague.
+ * @param {Record<string, unknown>} o
+ * @param {string} base
+ */
+function bareWebFmtErrAugment(o, base) {
+  const syscall = o.syscall
+  const code = o.code
+  const errno = o.errno
+  /** @type {string[]} */
+  const tail = []
+  if (typeof syscall === 'string' && syscall.trim()) tail.push('syscall=' + syscall)
+  if (code !== undefined && code !== null && String(code) !== '') tail.push(String(code))
+  if (errno !== undefined && errno !== null && String(errno) !== '')
+    tail.push('errno=' + String(errno))
+  const cause = o.cause
+  if (cause !== undefined && cause !== null) {
+    const cs = bareWebFmtErr(cause)
+    if (cs && cs !== 'unknown_error') tail.push('cause=(' + cs.slice(0, 240) + ')')
+  }
+  return tail.length ? base + ' [' + tail.join(', ') + ']' : base
+}
+
 /**
  * @param {Record<string, unknown>} ctx
  * @returns {typeof fetch | null}

kernel/etc/bare-os/posix_utilities.json

@@ -1,7 +1,7 @@
 {
   "schema": 2,
   "profileId": "bare-os-posix-like",
-  "generatedAt": "2026-04-22T05:30:18.374Z",
+  "generatedAt": "2026-04-22T05:38:34.635Z",
   "note": "Sparse POSIX Issue 7 coverage hints for /bin utilities. Omitted command names are not yet profiled here.",
   "commandIndex": [
     {

kernel/lib/bare/shell-completion.json

@@ -1,6 +1,6 @@
 {
   "schema": 1,
-  "atMs": 1776835818373,
+  "atMs": 1776836314634,
   "commands": [
     "agent",
     "arch",

package.json

@@ -32,7 +32,8 @@
     "lint": "prettier --check .",
     "os:seeder": "npm run build -w bare-os-coreutils && npm run build -w bare-os-openssh && npm run build -w bare-os-bare-libs && node scripts/ensure-pear-node-modules.mjs packages/bare-os-seeder && cd packages/bare-os-seeder && pear run --dev .",
     "os:booter": "node scripts/ensure-pear-node-modules.mjs packages/bare-os-booter && cd packages/bare-os-booter && pear run --dev .",
-    "vendor:bare-node-shims": "node scripts/vendor-bare-node-shims.mjs"
+    "vendor:bare-node-shims": "node scripts/vendor-bare-node-shims.mjs",
+    "smoke:agent-web-fetch:bare": "bare scripts/smoke-agent-web-fetch-bare.mjs"
   },
   "engines": {
     "node": ">=20"

packages/bare-os-coreutils/lib/agent-web-fetch.js

@@ -5,20 +5,37 @@
  * @returns {string}
  */
 function bareWebFmtErr(e) {
-  if (e == null) return '(null)'
+  if (e === undefined)
+    return 'promise_rejected_with_undefined (no rejection reason)'
+  if (e === null) return 'promise_rejected_with_null'
   if (typeof e === 'string') return e
   if (typeof e !== 'object') return String(e)
   const o = /** @type {Record<string, unknown>} */ (e)
   const msg = o.message
-  if (typeof msg === 'string' && msg.trim()) return msg
-  if (typeof msg === 'number' || typeof msg === 'boolean') return String(msg)
+  if (typeof msg === 'string' && msg.trim()) return bareWebFmtErrAugment(o, msg.trim())
+  if (typeof msg === 'number' || typeof msg === 'boolean')
+    return bareWebFmtErrAugment(o, String(msg))
   const nm = o.name
   const code = o.code
+  const errno = o.errno
   /** @type {string[]} */
   const bits = []
   if (typeof nm === 'string' && nm.trim()) bits.push(nm)
   if (code !== undefined && code !== null && String(code) !== '')
     bits.push('code=' + String(code))
+  if (errno !== undefined && errno !== null && String(errno) !== '')
+    bits.push('errno=' + String(errno))
+  const cause = o.cause
+  if (cause !== undefined && cause !== null && cause !== e) {
+    const cs = bareWebFmtErr(cause)
+    if (cs && cs !== 'unknown_error') bits.push('cause=(' + cs.slice(0, 280) + ')')
+  }
+  const errs = o.errors
+  if (Array.isArray(errs) && errs.length) {
+    errs.slice(0, 5).forEach((sub, i) => {
+      bits.push('agg' + i + '=' + bareWebFmtErr(sub).slice(0, 120))
+    })
+  }
   if (bits.length) return bits.join(' ')
   try {
     const j = JSON.stringify(o)
@@ -37,6 +54,29 @@ function bareWebFmtErr(e) {
   return 'unknown_error'
 }
 
+/**
+ * Append errno/syscall from Node-ish errors when message alone is vague.
+ * @param {Record<string, unknown>} o
+ * @param {string} base
+ */
+function bareWebFmtErrAugment(o, base) {
+  const syscall = o.syscall
+  const code = o.code
+  const errno = o.errno
+  /** @type {string[]} */
+  const tail = []
+  if (typeof syscall === 'string' && syscall.trim()) tail.push('syscall=' + syscall)
+  if (code !== undefined && code !== null && String(code) !== '') tail.push(String(code))
+  if (errno !== undefined && errno !== null && String(errno) !== '')
+    tail.push('errno=' + String(errno))
+  const cause = o.cause
+  if (cause !== undefined && cause !== null) {
+    const cs = bareWebFmtErr(cause)
+    if (cs && cs !== 'unknown_error') tail.push('cause=(' + cs.slice(0, 240) + ')')
+  }
+  return tail.length ? base + ' [' + tail.join(', ') + ']' : base
+}
+
 /**
  * @param {Record<string, unknown>} ctx
  * @returns {typeof fetch | null}

packages/bare-os-coreutils/test/agent-web-fetch.test.mjs

@@ -145,9 +145,14 @@ test('bareWebRunTool truncates large body stream', async (t) => {
   t.ok(out.truncated)
 })
 
-test('bareWebFmtErr never stringifies undefined as text', async (t) => {
+test('bareWebFmtErr null/undefined and node-like errors', async (t) => {
   const s = loadSandbox()
   const fmt = /** @type {(e: unknown) => string} */ (s.bareWebFmtErr)
+  t.ok(fmt(null).includes('rejected_with_null'))
+  t.ok(fmt(undefined).includes('rejected_with_undefined'))
   t.absent(fmt({ message: undefined }) === 'undefined')
   t.ok(fmt({ name: 'TypeError', code: 'ETIMEDOUT' }).includes('ETIMEDOUT'))
+  const withCause = new Error('outer')
+  withCause.cause = new Error('inner')
+  t.ok(fmt(withCause).includes('inner'))
 })

packages/bare-os-seeder/kernel/bin/agent

@@ -1670,20 +1670,37 @@ async function bareAgentCompleteOnce(opts) {
  * @returns {string}
  */
 function bareWebFmtErr(e) {
-  if (e == null) return '(null)'
+  if (e === undefined)
+    return 'promise_rejected_with_undefined (no rejection reason)'
+  if (e === null) return 'promise_rejected_with_null'
   if (typeof e === 'string') return e
   if (typeof e !== 'object') return String(e)
   const o = /** @type {Record<string, unknown>} */ (e)
   const msg = o.message
-  if (typeof msg === 'string' && msg.trim()) return msg
-  if (typeof msg === 'number' || typeof msg === 'boolean') return String(msg)
+  if (typeof msg === 'string' && msg.trim()) return bareWebFmtErrAugment(o, msg.trim())
+  if (typeof msg === 'number' || typeof msg === 'boolean')
+    return bareWebFmtErrAugment(o, String(msg))
   const nm = o.name
   const code = o.code
+  const errno = o.errno
   /** @type {string[]} */
   const bits = []
   if (typeof nm === 'string' && nm.trim()) bits.push(nm)
   if (code !== undefined && code !== null && String(code) !== '')
     bits.push('code=' + String(code))
+  if (errno !== undefined && errno !== null && String(errno) !== '')
+    bits.push('errno=' + String(errno))
+  const cause = o.cause
+  if (cause !== undefined && cause !== null && cause !== e) {
+    const cs = bareWebFmtErr(cause)
+    if (cs && cs !== 'unknown_error') bits.push('cause=(' + cs.slice(0, 280) + ')')
+  }
+  const errs = o.errors
+  if (Array.isArray(errs) && errs.length) {
+    errs.slice(0, 5).forEach((sub, i) => {
+      bits.push('agg' + i + '=' + bareWebFmtErr(sub).slice(0, 120))
+    })
+  }
   if (bits.length) return bits.join(' ')
   try {
     const j = JSON.stringify(o)
@@ -1702,6 +1719,29 @@ function bareWebFmtErr(e) {
   return 'unknown_error'
 }
 
+/**
+ * Append errno/syscall from Node-ish errors when message alone is vague.
+ * @param {Record<string, unknown>} o
+ * @param {string} base
+ */
+function bareWebFmtErrAugment(o, base) {
+  const syscall = o.syscall
+  const code = o.code
+  const errno = o.errno
+  /** @type {string[]} */
+  const tail = []
+  if (typeof syscall === 'string' && syscall.trim()) tail.push('syscall=' + syscall)
+  if (code !== undefined && code !== null && String(code) !== '') tail.push(String(code))
+  if (errno !== undefined && errno !== null && String(errno) !== '')
+    tail.push('errno=' + String(errno))
+  const cause = o.cause
+  if (cause !== undefined && cause !== null) {
+    const cs = bareWebFmtErr(cause)
+    if (cs && cs !== 'unknown_error') tail.push('cause=(' + cs.slice(0, 240) + ')')
+  }
+  return tail.length ? base + ' [' + tail.join(', ') + ']' : base
+}
+
 /**
  * @param {Record<string, unknown>} ctx
  * @returns {typeof fetch | null}

packages/bare-os-seeder/kernel/etc/bare-os/posix_utilities.json

@@ -1,7 +1,7 @@
 {
   "schema": 2,
   "profileId": "bare-os-posix-like",
-  "generatedAt": "2026-04-22T05:30:18.374Z",
+  "generatedAt": "2026-04-22T05:38:34.635Z",
   "note": "Sparse POSIX Issue 7 coverage hints for /bin utilities. Omitted command names are not yet profiled here.",
   "commandIndex": [
     {

packages/bare-os-seeder/kernel/lib/bare/shell-completion.json

@@ -1,6 +1,6 @@
 {
   "schema": 1,
-  "atMs": 1776835818373,
+  "atMs": 1776836314634,
   "commands": [
     "agent",
     "arch",

scripts/smoke-agent-web-fetch-bare.mjs

@@ -0,0 +1,134 @@
+#!/usr/bin/env bare
+/**
+ * Smoke-test agent-web-fetch under the Bare runtime (loads lib via bare-fs, evaluates helpers).
+ *
+ * From repo root (after coreutils build):
+ *   bare scripts/smoke-agent-web-fetch-bare.mjs
+ *
+ * Requires: npm install (bare-fetch, bare-fs, bare-abort-controller, b4a).
+ */
+import 'bare-abort-controller/global'
+import fetch from 'bare-fetch'
+import { readFile } from 'bare-fs/promises'
+import b4a from 'b4a'
+
+const agentWebFetchUrl = new URL(
+  '../packages/bare-os-coreutils/lib/agent-web-fetch.js',
+  import.meta.url
+)
+
+/** Minimal TextDecoder for bareWebDecodeBytes (Bare has no global TextDecoder). */
+class TextDecoderPolyfill {
+  /**
+   * @param {string} [_label]
+   * @param {unknown} [_opts]
+   */
+  constructor(_label, _opts) {}
+  /**
+   * @param {Uint8Array} bytes
+   */
+  decode(bytes) {
+    return b4a.toString(bytes)
+  }
+}
+
+async function main() {
+  let buf = await readFile(agentWebFetchUrl)
+  let code =
+    typeof buf === 'string' ? buf : b4a.toString(buf)
+
+  /** @type {typeof bareEditSgr | undefined} */
+  function bareEditSgr(cls, on) {
+    if (!on) return ''
+    switch (cls) {
+      case 'keyword':
+        return '\x1b[36m'
+      case 'string':
+        return '\x1b[32m'
+      case 'comment':
+        return '\x1b[90m'
+      case 'number':
+        return '\x1b[33m'
+      case 'dim':
+        return '\x1b[2m'
+      default:
+        return ''
+    }
+  }
+  const EDIT_ANSI_RESET = '\x1b[0m'
+
+  const sandbox = {
+    URL,
+    TextDecoder:
+      typeof globalThis.TextDecoder !== 'undefined'
+        ? globalThis.TextDecoder
+        : TextDecoderPolyfill,
+    TextEncoder:
+      typeof globalThis.TextEncoder !== 'undefined'
+        ? globalThis.TextEncoder
+        : /** @type {unknown} */ (undefined),
+    Uint8Array,
+    AbortController: globalThis.AbortController,
+    AbortSignal: globalThis.AbortSignal,
+    ReadableStream:
+      typeof globalThis.ReadableStream !== 'undefined'
+        ? globalThis.ReadableStream
+        : /** @type {unknown} */ (undefined),
+    Response:
+      typeof globalThis.Response !== 'undefined'
+        ? globalThis.Response
+        : /** @type {unknown} */ (undefined),
+    Request:
+      typeof globalThis.Request !== 'undefined'
+        ? globalThis.Request
+        : /** @type {unknown} */ (undefined),
+    console,
+    bareEditSgr,
+    EDIT_ANSI_RESET,
+    fetch,
+    globalThis
+  }
+
+  const fn = new Function(
+    ...Object.keys(sandbox),
+    code +
+      '\n;return { bareWebFmtErr, bareWebRunTool };'
+  )
+  const out = fn(...Object.values(sandbox))
+  const bareWebFmtErrFn = out.bareWebFmtErr
+  const bareWebRunToolFn = out.bareWebRunTool
+
+  if (typeof bareWebFmtErrFn !== 'function')
+    throw new Error('bareWebFmtErr not defined after eval')
+
+  console.log('[smoke-bare-web-fetch] bareWebFmtErr(null)=', bareWebFmtErrFn(null))
+  console.log(
+    '[smoke-bare-web-fetch] bareWebFmtErr(undefined)=',
+    bareWebFmtErrFn(undefined)
+  )
+
+  if (typeof bareWebRunToolFn !== 'function') {
+    console.log('[smoke-bare-web-fetch] skip bareWebRunTool')
+    return
+  }
+
+  const result = await bareWebRunToolFn({
+    ctx: { httpFetch: fetch },
+    url: 'https://example.com/',
+    format: 'meta',
+    timeout_ms: 15000,
+    max_response_bytes: 65536
+  })
+  console.log('[smoke-bare-web-fetch] https://example.com ok=', result.ok)
+  if (!result.ok) console.log('[smoke-bare-web-fetch] error=', result.error)
+  else {
+    console.log('[smoke-bare-web-fetch] status=', result.status)
+    console.log('[smoke-bare-web-fetch] extract.title=', result.extract?.title)
+  }
+}
+
+main().catch((e) => {
+  console.error('[smoke-bare-web-fetch] fatal', e)
+  if (typeof globalThis.process !== 'undefined')
+    /** @type {{ exitCode?: number }} */ (globalThis.process).exitCode = 1
+})