> ## Documentation Index
> Fetch the complete documentation index at: https://docs.nexrex.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# AI coach

> Chat with your coach and get insight after every run.

The NexRex AI coach answers training questions, explains your plan, and reviews
each activity you complete.

## Ask anything

Open the coach chat to ask about pacing, recovery, race strategy, or why a
workout is on your calendar.

## Post-run insights

After an activity syncs, NexRex generates a short read on how it went — effort,
pacing, and what it means for upcoming sessions.

<Tip>
  Insights are most useful when your heart-rate data is present. Make sure your
  [connected device](/athletes/connect-device) records HR.
</Tip>

## Workout drafts in chat

When you ask Rex to build or adjust a workout in chat, the reply now appears as
a structured **workout-draft card** directly inside the conversation instead of
plain text. The card gives you a scannable preview of what Rex came up with
before anything is saved to your plan.

Each card shows:

* A title and short subtitle summarising the session.
* A **status pill** — for example **Draft**, **Review**, **Ready**, or
  **Error** — so you can tell at a glance whether Rex still needs input.
* **Nested workout blocks** with steps, durations, distances, and rounds for
  any repeats.
* Session totals, so you can see overall duration and volume without expanding
  every block.

### Clarifying an ambiguous request

If Rex isn't sure how to interpret part of your request — for example whether
"4 × 1k" should be at threshold or interval pace — the card surfaces an
**ambiguity panel** with tappable **choice chips**. Pick the option that
matches what you had in mind and Rex updates the draft in place.

<Note>
  Workout-draft cards are rolling out gradually. Until the feature reaches your
  account, Rex's workout suggestions continue to appear as text in chat. You
  don't need to change anything in **Settings** — the richer card view turns on
  automatically once the rollout includes you.
</Note>

## Fast and Pro models

Rex offers two response models you can switch between from the app bar in the
Rex chat tab: **Fast** and **Pro**. Fast is optimized for quick replies; Pro
uses a more capable model for deeper reasoning on complex questions — planning
tweaks, race strategy, or interpreting several weeks of training at once.

### Choose a model

1. Open the **Rex** tab in chat (the model selector doesn't appear on the
   direct-message conversation with your human coach).
2. Tap the model name in the app bar — **Fast** or **Pro**.
3. Pick the option you want. Your choice is remembered across sessions and
   applies to every message you send until you change it again.

### Who gets Pro

Pro is a [Pro-subscription](/account/subscriptions) feature and is also
available to coaches on any active plan.

* **Coaches and Pro subscribers** default to Pro and can switch to Fast at any
  time.
* **Everyone else** defaults to Fast. The Pro option is visible but locked
  with a **PRO** badge — tapping it opens the standard subscription paywall
  instead of switching the model.

If your Pro entitlement lapses, Rex automatically falls back to Fast on your
next message, even if Pro was your last saved choice. Re-subscribe and Pro
becomes selectable again.

## Choose your AI coach

If your coach has published one or more AI coach agents to your organization,
you can pick which one answers you in chat. The picker is only visible when
that catalog is available for your org — otherwise the entry stays hidden and
Rex uses the default coach automatically.

### Open the picker

1. Open the NexRex app.
2. Go to **Settings**.
3. Tap **AI 教練** (**AI Coach**).

### What you'll see

The screen lists every AI coach agent your organization has published, plus a
built-in **Default AI Coach** option at the top. Each entry shows the agent's
display name, a short summary, its coaching style, and any specialties the
coach tagged it with. The currently selected agent is marked so you can tell
at a glance which one you're chatting with.

If the list can't load, you'll see *AI coaches are unavailable right now.
Please try again later.* instead of an empty screen.

### Switch coaches

1. Tap the agent you want to use.
2. Wait for the confirmation snackbar (**AI Coach updated to *\<name>***).

The selection only changes after the save completes. If the save fails, your
previous coach stays active and you'll see an error snackbar — nothing changes
until a save succeeds.

### Default AI Coach

Picking **Default AI Coach** clears your personal choice. Chat then falls back
to whichever agent your organization has set as its default, or to the generic
NexRex coach if no organization default is configured. Use this if you want to
follow whatever your coach rolls out next without re-picking each time.

<Note>
  You can switch coaches at any time. Coach conversations may be reviewed by
  your organization to help improve service quality.
</Note>

## Rex's Memory

Rex's Memory is the editable store of durable facts your AI coach remembers
about you — goals, injuries, preferences, lifestyle constraints, and similar
context that should outlast a single chat. Editing this list changes how Rex
coaches you going forward.

<Note>
  Rex's Memory is rolling out gradually. If you don't see it under **Settings**
  yet, your account hasn't been switched on for the feature. The screen is
  available in English, Japanese, and Traditional Chinese.
</Note>

### Open Rex's Memory

1. Open the NexRex app.
2. Go to **Settings**.
3. Tap **Rex's Memory**.

### What you'll see

Memories are grouped by category — for example **Goals**, **Injury**,
**Preferences**, **Lifestyle**, **Communication**, **Equipment**, **Race
context**, and **Notes**. Each row shows:

* The memory text.
* A **provenance badge** indicating who added it:
  * **You** — you added it yourself.
  * **Coach** — your coach added it.
  * **Rex** — Rex picked it up from your chats.
* A **last-updated** label so you can tell how fresh each entry is.

If Rex hasn't learned anything durable yet, you'll see an empty state inviting
you to keep chatting or add a memory yourself.

### Add a memory

1. On the Rex's Memory screen, tap **Add memory**.
2. In the bottom-sheet form, pick a **Category** and type the **Memory** text
   (for example, *Prefers morning runs before work*).
3. Tap **Save**.

The new entry appears under its category with a **You** badge.

### Edit a memory

1. Tap the memory you want to change.
2. Update the category or text in the bottom-sheet form.
3. Tap **Save**.

The row's last-updated label refreshes to reflect your change.

### Delete a memory

1. Swipe the memory row from right to left.
2. Confirm **Forget** in the dialog that appears.

Choosing **Cancel** keeps the memory and slides the row back into place. Once
forgotten, Rex no longer uses that fact when coaching you, but you can always
add it back later.

<Tip>
  Keep memories specific and current — Rex uses them every time it plans or
  reviews your training, so out-of-date entries can pull your coaching in the
  wrong direction.
</Tip>