Function parseUserSpecifiedModel

src/utils/model/model.ts:558–640

(
  modelInput: ModelName | ModelAlias,
)

 * @param modelInput The model alias or name provided by the user.
 */
export function parseUserSpecifiedModel(
  modelInput: ModelName | ModelAlias,
): ModelName {
  const modelInputTrimmed = modelInput.trim()
  const normalizedModel = modelInputTrimmed.toLowerCase()

  const has1mTag = has1mContext(normalizedModel)
  const modelString = has1mTag
    ? normalizedModel.replace(/\[1m]$/i, '').trim()
    : normalizedModel

  // BYOK OpenAI-compat: the model id names a model on the user's own server and
  // must pass through verbatim. Never resolve it against the built-in NCODE
  // managed-model aliases — an id that collides with a reserved alias (e.g.
  // `glm-5.2`, `k2.7`) would otherwise be rewritten to an internal deployment
  // path the user's server does not recognize, causing a 404.
  if (!isOpenAICompatByokActive()) {
    const exactNcodeModel = resolveNCodeManagedModel(normalizedModel)
    if (exactNcodeModel) {
      return exactNcodeModel.model
    }
  }

  if (isModelAlias(modelString)) {
    switch (modelString) {
      case 'opusplan':
        return getDefaultOpusModel() + (has1mTag ? '[1m]' : '') // Opus-tier reasoning in plan mode
      case 'sonnet':
        return getDefaultFlashModel() + (has1mTag ? '[1m]' : '')
      case 'haiku':
        return getDefaultHaikuModel() + (has1mTag ? '[1m]' : '')
      case 'opus':
        return getDefaultOpusModel() + (has1mTag ? '[1m]' : '')
      case 'best':
        return getBestModel()
      default:
    }
  }

  // See the BYOK note above: managed-alias resolution is skipped entirely for
  // BYOK OpenAI-compat sessions so the user's model id is forwarded verbatim.
  if (!isOpenAICompatByokActive()) {
    const ncodeModel = resolveNCodeManagedModel(modelString)
    if (ncodeModel) {
      return ncodeModel.model
    }
  }

  // Opus 4/4.1 are no longer available on the first-party API (same as
  // the Anthropic first-party API) — silently remap to the current Opus default. The 'opus'
  // alias already resolves to 4.6, so the only users on these explicit
  // strings pinned them in settings/env/--model/SDK before 4.5 launched.
  // 3P providers may not yet have 4.6 capacity, so pass through unchanged.
  if (
    getAPIProvider() === 'firstParty' &&
    isLegacyOpusFirstParty(modelString) &&
    isLegacyModelRemapEnabled()
  ) {