feat: allow customizing context window and max output tokens

src/components/ProviderManager.test.tsx

@@ -961,13 +961,13 @@ test('ProviderManager clears hidden Hicap auth fields when editing', async () =>
     mounted.stdin.write('\r')
     await waitForFrameOutput(mounted.getOutput, frame =>
       frame.includes('Edit provider profile') &&
-      frame.includes('Step 1 of 6'),
+      frame.includes('Step 1 of 8'),
     )
 
-    for (let step = 2; step <= 6; step++) {
+    for (let step = 2; step <= 8; step++) {
       mounted.stdin.write('\r')
       await waitForFrameOutput(mounted.getOutput, frame =>
-        frame.includes(`Step ${step} of 6`),
+        frame.includes(`Step ${step} of 8`),
       )
     }
     mounted.stdin.write('\r')
@@ -1037,25 +1037,25 @@ test('ProviderManager skips advanced fields for legacy Kimi Code profiles', asyn
     await waitForFrameOutput(mounted.getOutput, frame =>
       frame.includes('Edit provider profile') &&
       frame.includes('Provider name') &&
-      frame.includes('Step 1 of 4'),
+      frame.includes('Step 1 of 6'),
     )
 
     mounted.stdin.write('\r')
     await waitForFrameOutput(mounted.getOutput, frame =>
       frame.includes('Base URL') &&
-      frame.includes('Step 2 of 4'),
+      frame.includes('Step 2 of 6'),
     )
 
     mounted.stdin.write('\r')
     await waitForFrameOutput(mounted.getOutput, frame =>
       frame.includes('Default model') &&
-      frame.includes('Step 3 of 4'),
+      frame.includes('Step 3 of 6'),
     )
 
     mounted.stdin.write('\r')
     const output = await waitForFrameOutput(mounted.getOutput, frame =>
       frame.includes('API key') &&
-      frame.includes('Step 4 of 4'),
+      frame.includes('Step 4 of 6'),
     )
 
     expect(output).not.toContain('API mode')
@@ -1798,49 +1798,61 @@ test('ProviderManager editing an active multi-model provider keeps app state on
     mounted.getOutput,
     frame =>
       frame.includes('Edit provider profile') &&
-      frame.includes('Step 1 of 8'),
+      frame.includes('Step 1 of 10'),
+  )
+
+  mounted.stdin.write('\r')
+  await waitForFrameOutput(
+    mounted.getOutput,
+    frame => frame.includes('Step 2 of 10'),
+  )
+
+  mounted.stdin.write('\r')
+  await waitForFrameOutput(
+    mounted.getOutput,
+    frame => frame.includes('Step 3 of 10'),
   )
 
   mounted.stdin.write('\r')
   await waitForFrameOutput(
     mounted.getOutput,
-    frame => frame.includes('Step 2 of 8'),
+    frame => frame.includes('Step 4 of 10'),
   )
 
   mounted.stdin.write('\r')
   await waitForFrameOutput(
     mounted.getOutput,
-    frame => frame.includes('Step 3 of 8'),
+    frame => frame.includes('Step 5 of 10'),
   )
 
   mounted.stdin.write('\r')
   await waitForFrameOutput(
     mounted.getOutput,
-    frame => frame.includes('Step 4 of 8'),
+    frame => frame.includes('Step 6 of 10'),
   )
 
   mounted.stdin.write('\r')
   await waitForFrameOutput(
     mounted.getOutput,
-    frame => frame.includes('Step 5 of 8'),
+    frame => frame.includes('Step 7 of 10'),
   )
 
   mounted.stdin.write('\r')
   await waitForFrameOutput(
     mounted.getOutput,
-    frame => frame.includes('Step 6 of 8'),
+    frame => frame.includes('Step 8 of 10'),
   )
 
   mounted.stdin.write('\r')
   await waitForFrameOutput(
     mounted.getOutput,
-    frame => frame.includes('Step 7 of 8'),
+    frame => frame.includes('Step 9 of 10'),
   )
 
   mounted.stdin.write('\r')
   await waitForFrameOutput(
     mounted.getOutput,
-    frame => frame.includes('Step 8 of 8'),
+    frame => frame.includes('Step 10 of 10'),
   )
 
   mounted.stdin.write('\r')

src/components/ProviderManager.tsx

@@ -111,6 +111,8 @@ type DraftField =
   | 'authHeader'
   | 'authHeaderValue'
   | 'customHeaders'
+  | 'contextWindowSize'
+  | 'maxOutputTokens'
 
 type ProviderDraft = Record<DraftField, string>
 
@@ -194,6 +196,20 @@ const FORM_STEPS: Array<{
     helpText: 'Optional. Extra non-auth request headers for providers that support them.',
     optional: true,
   },
+  {
+    key: 'contextWindowSize',
+    label: 'Context window size',
+    placeholder: 'e.g. 128000',
+    helpText: 'Optional. Max tokens for context (input + output + history).',
+    optional: true,
+  },
+  {
+    key: 'maxOutputTokens',
+    label: 'Max output tokens',
+    placeholder: 'e.g. 4096',
+    helpText: 'Optional. Max tokens the model can generate in a single turn.',
+    optional: true,
+  },
 ]
 
 const GITHUB_PROVIDER_ID = '__github_models__'
@@ -215,6 +231,8 @@ function toDraft(profile: ProviderProfile): ProviderDraft {
     authHeader: profile.authHeader ?? '',
     authHeaderValue: profile.authHeaderValue ?? '',
     customHeaders: serializeProfileCustomHeaders(profile.customHeaders) ?? '',
+    contextWindowSize: profile.contextWindowSize ? String(profile.contextWindowSize) : '',
+    maxOutputTokens: profile.maxOutputTokens ? String(profile.maxOutputTokens) : '',
   }
 }
 
@@ -251,6 +269,8 @@ function presetToDraft(preset: ProviderPreset): ProviderDraft {
     authHeader: '',
     authHeaderValue: '',
     customHeaders: '',
+    contextWindowSize: '',
+    maxOutputTokens: '',
   }
 }
 
@@ -282,7 +302,13 @@ function profileSummary(profile: ProviderProfile, isActive: boolean): string {
     routeSupportsAuthHeaders(routeId) && profile.authHeader
       ? ` · ${profile.authHeader} auth`
       : ''
-  return `${providerKind} · ${profile.baseUrl} · ${modelDisplay}${modeInfo}${authInfo} · ${keyInfo}${activeSuffix}`
+  const contextInfo = profile.contextWindowSize
+    ? ` · ${Math.round(profile.contextWindowSize / 1000)}k ctx`
+    : ''
+  const tokensInfo = profile.maxOutputTokens
+    ? ` · ${profile.maxOutputTokens} out`
+    : ''
+  return `${providerKind} · ${profile.baseUrl} · ${modelDisplay}${modeInfo}${authInfo}${contextInfo}${tokensInfo} · ${keyInfo}${activeSuffix}`
 }
 
 function getGithubCredentialSourceFromEnv(
@@ -1229,6 +1255,12 @@ export function ProviderManager({ mode, onDone }: Props): React.ReactNode {
         Object.keys(parsedCustomHeaders.headers).length > 0
           ? parsedCustomHeaders.headers
           : undefined,
+      contextWindowSize: nextDraft.contextWindowSize
+        ? parseInt(nextDraft.contextWindowSize, 10)
+        : undefined,
+      maxOutputTokens: nextDraft.maxOutputTokens
+        ? parseInt(nextDraft.maxOutputTokens, 10)
+        : undefined,
     }
 
     const saved = profileId
@@ -1469,6 +1501,18 @@ export function ProviderManager({ mode, onDone }: Props): React.ReactNode {
       return
     }
 
+    if (
+      (currentStepKey === 'contextWindowSize' ||
+        currentStepKey === 'maxOutputTokens') &&
+      trimmed.length > 0
+    ) {
+      const parsed = parseInt(trimmed, 10)
+      if (isNaN(parsed) || parsed <= 0) {
+        setErrorMessage(`${currentStep.label} must be a positive number.`)
+        return
+      }
+    }
+
     const nextDraft = {
       ...draft,
       [currentStepKey]: trimmed,

src/services/api/utils.ts

@@ -0,0 +1,168 @@
+import { isIP } from 'node:net'
+import { logForDebugging } from '../../utils/debug.js'
+import { isCodexAlias } from '../../utils/model/modelDescriptor.js'
+
+// Reads an env-var-style string intended as a URL or path, rejecting both
+// empty strings and the literal string "undefined" that Windows shells can
+// write when a variable is unset-then-referenced without quotes (issue #336).
+export function asEnvUrl(value: string | undefined): string | undefined {
+  if (!value) return undefined
+  const trimmed = value.trim()
+  if (!trimmed) return undefined
+  if (trimmed === 'undefined') {
+    return undefined
+  }
+  return trimmed
+}
+
+const warnedUndefinedEnvNames = new Set<string>()
+
+export function asNamedEnvUrl(
+  value: string | undefined,
+  envName: string,
+): string | undefined {
+  if (!value) return undefined
+
+  const trimmed = value.trim()
+  if (!trimmed) return undefined
+
+  if (trimmed === 'undefined') {
+    if (!warnedUndefinedEnvNames.has(envName)) {
+      warnedUndefinedEnvNames.add(envName)
+      logForDebugging(
+        `[provider-config] Environment variable ${envName} is the literal string "undefined"; ignoring it.`,
+        { level: 'warn' },
+      )
+    }
+    return undefined
+  }
+
+  return trimmed
+}
+
+export function isCodexBaseUrl(baseUrl: string | undefined): boolean {
+  if (!baseUrl) return false
+  try {
+    const parsed = new URL(baseUrl)
+    return (
+      parsed.hostname === 'chatgpt.com' &&
+      parsed.pathname.replace(/\/+$/, '') === '/backend-api/codex'
+    )
+  } catch {
+    return false
+  }
+}
+
+export function shouldUseCodexTransport(
+  model: string,
+  baseUrl: string | undefined,
+): boolean {
+  const explicitBaseUrl = asEnvUrl(baseUrl)
+  return isCodexBaseUrl(explicitBaseUrl) || (!explicitBaseUrl && isCodexAlias(model))
+}
+
+export function getGithubEndpointType(
+  baseUrl: string | undefined,
+): 'copilot' | 'models' | 'custom' {
+  if (!baseUrl) return 'copilot'
+  try {
+    const hostname = new URL(baseUrl).hostname.toLowerCase()
+    if (hostname === 'api.githubcopilot.com') {
+      return 'copilot'
+    }
+    if (hostname === 'models.github.ai' || hostname.endsWith('.github.ai')) {
+      return 'models'
+    }
+    return 'custom'
+  } catch {
+    return 'copilot'
+  }
+}
+
+const LOCALHOST_HOSTNAMES = new Set(['localhost', '127.0.0.1', '::1'])
+
+function isPrivateIpv4Address(hostname: string): boolean {
+  const octets = hostname.split('.').map(part => Number.parseInt(part, 10))
+  if (octets.length !== 4 || octets.some(octet => Number.isNaN(octet))) {
+    return false
+  }
+
+  return (
+    octets[0] === 10 ||
+    (octets[0] === 172 && octets[1] >= 16 && octets[1] <= 31) ||
+    (octets[0] === 192 && octets[1] === 168)
+  )
+}
+
+function isPrivateIpv6Address(hostname: string): boolean {
+  const firstHextet = hostname.split(':', 1)[0]
+  if (!firstHextet) return false
+
+  const prefix = Number.parseInt(firstHextet, 16)
+  if (Number.isNaN(prefix)) return false
+
+  return (prefix & 0xfe00) === 0xfc00 || (prefix & 0xffc0) === 0xfe80
+}
+
+export function isLocalProviderUrl(baseUrl: string | undefined): boolean {
+  if (!baseUrl) return false
+  try {
+    let hostname = new URL(baseUrl).hostname.toLowerCase()
+
+    // Strip IPv6 brackets added by the URL parser (e.g. "[::1]" -> "::1")
+    if (hostname.startsWith('[') && hostname.endsWith(']')) {
+      hostname = hostname.slice(1, -1)
+    }
+
+    // Strip RFC6874 IPv6 zone identifiers (e.g. "fe80::1%25en0" -> "fe80::1")
+    const zoneIdIndex = hostname.indexOf('%25')
+    if (zoneIdIndex !== -1) {
+      hostname = hostname.slice(0, zoneIdIndex)
+    }
+
+    if (LOCALHOST_HOSTNAMES.has(hostname) || hostname === '0.0.0.0') {
+      return true
+    }
+    if (hostname.endsWith('.local')) {
+      return true
+    }
+
+    const ipVersion = isIP(hostname)
+    if (ipVersion === 4) {
+      // Treat the full 127.0.0.0/8 loopback range as local
+      const firstOctet = Number.parseInt(hostname.split('.', 1)[0] ?? '', 10)
+      return firstOctet === 127 || isPrivateIpv4Address(hostname)
+    }
+    if (ipVersion === 6) {
+      return isPrivateIpv6Address(hostname)
+    }
+
+    return false
+  } catch {
+    return false
+  }
+}
+
+export function parseOpenAICompatibleApiFormat(
+  value: string | undefined,
+): 'chat_completions' | 'responses' | undefined {
+  if (!value) return undefined
+  const normalized = value.trim().toLowerCase().replace(/[- ]+/g, '_')
+  if (
+    normalized === 'responses' ||
+    normalized === 'response' ||
+    normalized === 'responses_api'
+  ) {
+    return 'responses'
+  }
+  if (
+    normalized === 'chat_completions' ||
+    normalized === 'chat_completion' ||
+    normalized === 'completions' ||
+    normalized === 'completion' ||
+    normalized === 'chat'
+  ) {
+    return 'chat_completions'
+  }
+  return undefined
+}

src/utils/config.ts

@@ -200,6 +200,8 @@ export type ProviderProfile = {
   authScheme?: OpenAICompatibleAuthScheme
   authHeaderValue?: string
   customHeaders?: Record<string, string>
+  contextWindowSize?: number
+  maxOutputTokens?: number
 }
 
 export type GlobalConfig = {