Once a user has touched a field, it is better to leave it alone and display explicit validation errors over silently overwriting their inputs. Same for auto-filled values (whether from query parameters or a previous build).
React's [Why You Might Not Need An
Effect](https://react.dev/learn/you-might-not-need-an-effect) article
describes several antipatterns and footguns you might encounter when
working with useEffect, so I fed it to an agent and let it determine
some low hanging fruit to fix:
Replace useEffect+setState patterns with direct computations where the
values are purely derived from props, state, or query data:
- useWebpushNotifications: derive `enabled` inline from query data
instead of setting it via useEffect
- ProxyContext: replace `proxy` state + updateProxy callback + useEffect
with a single useMemo over its three inputs
- useSyncFormParameters: replace ref-sync useEffect with direct
assignment during render
- AgentsSidebar (LoadMoreSentinel): replace two ref-sync useEffects with
direct assignments during render
Co-authored by Coder Agent 🤖
## Problem
Flaky e2e test: `update workspace, new required, mutable parameter
added`
```
Error: Timed out 15000ms waiting for expect(locator).toHaveValue(expected)
Locator: getByTestId('parameter-field-Sixth parameter').locator('input')
Expected string: "99"
Received string: ""
```
## Root Cause
When the workspace parameters page loads, the WebSocket sends an initial
response with template defaults. For parameters with no default (like
`sixth_parameter`), the server returns `{valid: false, value: ""}`. On
first render, `useSyncFormParameters` sees this invalid server value and
overwrites the form's correctly-autofilled value ("99" from the previous
build) with "".
## Fix
When the server value is `{valid: false}`, preserve the current form
value instead of overwriting with "". This prevents the sync hook from
clobbering autofilled values before the server has had a chance to
process them.
## Verification
- TypeScript: zero type errors
- Biome lint: clean
- Unit tests: 2/2 passing
- **E2E soak test: 849/854 passed across 854 runs (99.5% pass rate)**
- 0 occurrences of the original flake (empty value on settings page)
- 5 residual failures are a separate pre-existing race in
`fillParameters` where user input is overwritten during the 500ms
debounce window
Asher