Support Prerendering

What it does

When your agent uses it

• Fixing duplicate data loads
• UI flicker during prerender-to-interactive handoff
• Null references during prerender
• Persisting state across prerender

Example prompts

• “/support-prerendering”

Workflow steps

4 steps, taken from the first numbered list in SKILL.md.

1. 1Register a matching service on the server — both Program.cs files provide the service
2. 2Make the service optional — use constructor injection with a nullable default: public MyComponent(IMyService? svc = null)
3. 3Create a service abstraction — interface in .Client, implementations in both projects
4. 4Disable prerendering for that component

What it can do on your machine

Read from SKILL.md and the folder at commit 8d670fa. It shows what the files ask for, not the result of running them.

• Tool permissions

  Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.

  From allowed-tools in the SKILL.md frontmatter.

• Runs code

  No scripts in the folder and no shell commands in SKILL.md (its code samples are razor and csharp).

  From the folder's file list and the shell code blocks in SKILL.md.

• Network

  No URLs in SKILL.md.

  From URLs in SKILL.md, links to its own repository left out.

• Credentials

  Names no API keys, tokens, secrets or passwords.

  From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

Support Prerendering loads about 1.8k tokens when it runs. Until then it costs about 126 tokens; SKILL.md has 553 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it

~126

When it runs · the whole SKILL.md, loaded when a task matches

~1.8k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from dotnet/skills at commit 8d670fa, republished under its MIT licence (© dotnet). 553 words, ~1,828 tokens.

name

support-prerendering

description

Make interactive Blazor components work correctly with prerendering. USE FOR fixing duplicate data loads, UI flicker during prerender-to-interactive handoff, null references during prerender, persisting state across prerender, disabling prerendering, excluding pages from interactive routing, or detecting whether a component is currently prerendering. DO NOT USE for choosing which render mode to use (see create-blazor-project) or general component authoring (see author-component).

license

MIT

@page "/forecasts"
@rendermode InteractiveServer

<h1>Weather</h1>

@if (Forecasts is null)
{
    <p>Loading...</p>
}
else
{
    @foreach (var f in Forecasts)
    {
        <p>@f.Date: @f.TemperatureC°C</p>
    }
}

@code {
    [PersistentState]
    public WeatherForecast[]? Forecasts { get; set; }

    protected override async Task OnInitializedAsync()
    {
        Forecasts ??= await ForecastService.GetForecastsAsync();
    }
}

@foreach (var item in items)
{
    <ItemCard @key="item.Id" />
}

@inject PersistentComponentState ApplicationState

@code {
    private List<Order>? orders;

    protected override async Task OnInitializedAsync()
    {
        ApplicationState.RegisterOnPersisting(PersistOrders);

        if (!ApplicationState.TryTakeFromJson<List<Order>>("orders", out var restored))
        {
            orders = await OrderService.GetOrdersAsync();
        }
        else
        {
            orders = restored;
        }
    }

    private Task PersistOrders()
    {
        ApplicationState.PersistAsJson("orders", orders);
        return Task.CompletedTask;
    }
}

@rendermode @(new InteractiveServerRenderMode(prerender: false))

<MyChart @rendermode="new InteractiveServerRenderMode(prerender: false)" />

<HeadOutlet @rendermode="new InteractiveServerRenderMode(prerender: false)" />
<Routes @rendermode="new InteractiveServerRenderMode(prerender: false)" />

@page "/privacy"
@attribute [ExcludeFromInteractiveRouting]

<h1>Privacy Policy</h1>

<!DOCTYPE html>
<html>
<head>
    <HeadOutlet @rendermode="RenderModeForPage" />
</head>
<body>
    <Routes @rendermode="RenderModeForPage" />
    <script src="_framework/blazor.web.js"></script>
</body>
</html>

@code {
    [CascadingParameter]
    public HttpContext HttpContext { get; set; } = default!;

    private IComponentRenderMode? RenderModeForPage =>
        HttpContext.AcceptsInteractiveRouting() ? InteractiveServer : null;
}

protected override async Task OnInitializedAsync()
{
    if (RendererInfo.IsInteractive)
    {
        // Only runs during the interactive render, not during prerender
        await StartSignalRConnection();
    }
}

© dotnet, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file

Files

Just SKILL.md in plugins/dotnet-blazor/skills/support-prerendering of dotnet/skills.

Open the folder on GitHubat commit 8d670fa

Used in 1 other repository

We found 2 copies of this SKILL.md (exact, near-identical or edited) in other folders, from 1 other GitHub owner. This page covers the copy in dotnet/skills, which our catalogue first saw on October 7, 2026.

• managedcode/dotnet-skillscatalog/Frameworks/Official-DotNet-Blazor/skills/support-prerenderingexternal-sources/upstreams/dotnet-skills/plugins/dotnet-blazor/skills/support-prerendering