# Downgrade the model when budget is tight (/docs/recipes/downgrade-model)
Instead of blocking a user when their budget runs out, keep them working on a cheaper model. A
**Reroute** rule swaps the model before the call is dispatched, so your app never sees the
difference.
## The rule [#the-rule]
On the Firewall page, **Cost & access** tab, click **New rule from template** and pick a
**Save money** card:
**Switch to a cheaper model after $X** — the budget-gated version. Set the amount you want to
switch after, the reset period, and the cheaper model. Until the pool crosses that limit, calls
run normally.
**Send free users to a cheaper model** — the unconditional version. No limit at all: *every* call
on the plan you name is swapped, from the first one. There are per-team and per-session variants
too (*Switch each team or feature to a cheaper model after $X*, *Switch a session to a cheaper
model after $X*).
**Same-provider swaps only** — pick a smaller or cheaper model from the same provider. A
cross-provider target is rejected. The target also has to be a model TokenPolice already has
pricing for, or the rule won't save.
Reroute does not switch the model on some frameworks — including LangChain, LangGraph,
LlamaIndex, Pydantic AI, and the Vercel AI SDK. Those calls still run on the original model.
Confirm a swap actually happens in your app before you enforce this in production.
## The snippet [#the-snippet]
There's **nothing to change in your request code** — the SDK rewrites the model and your
`create()` call returns from the cheaper model as normal. The only requirement is that your app
runs in enforce, since reroute (like block) only acts when both dials say enforce:
```python
import token_police as tp
tp.init(
api_key=os.environ["TOKENPOLICE_API_KEY"],
base_url="https://collect.tokenpolice.ai",
firewall="enforce", # in dry_run the reroute is only recorded, not applied
)
```
```typescript
import { init } from "token-police";
init({
apiKey: process.env.TOKENPOLICE_API_KEY!,
baseUrl: "https://collect.tokenpolice.ai",
firewall: "enforce",
});
```
A reroute never silently unpins a model you asked for: if the target resolves to the same model
you already requested, nothing is swapped.
In Dry-run the rule records a *"Would reroute…"* projection instead of acting, so you can see how
often it would fire before you turn it on — check it in the [dashboard](/docs/dashboard). See
[Actions](/docs/rules/actions#reroute).
## Next [#next]