How to Customize the System Prompt and Citation Formatting in MiniSearch

You can customize the system prompt and citation formatting in MiniSearch by editing the systemPrompt template in client/modules/settings.ts and modifying the getFormattedSearchResults() function in client/modules/textGenerationUtilities.ts to control how search results appear to the LLM.

MiniSearch is an open-source AI search interface that exposes its prompt assembly logic through user-editable settings and modular utility functions. The repository felladrin/minisearch separates prompt templates from result formatting, allowing you to tailor both the assistant's personality and citation style without touching core generation logic.

Where the System Prompt Template Lives

The default prompt is defined in client/modules/settings.ts as the systemPrompt property of defaultSettings. This template uses placeholder syntax for dynamic values:

systemPrompt: `Answer using the search results below as your primary source, supplemented by your own knowledge when needed. … 
Below are the search results fetched at {{currentDate}}.

{{searchResults}}`,

The template contains two key placeholders:

• {{searchResults}} — Replaced with formatted search results at runtime
• {{currentDate}} or {{dateTime}} — Replaced with the current date in en-CA format

Source: client/modules/settings.ts:19-27

Runtime Prompt Assembly

When processing a query, client/modules/systemPrompt.ts interpolates the template through the getSystemPrompt() function:

export function getSystemPrompt(searchResults: string) {
  const currentDate = new Intl.DateTimeFormat("en-CA", {
    year: "numeric",
    month: "2-digit",
    day: "2-digit",
  }).format(new Date());

  return getSettings()
    .systemPrompt.replace("{{searchResults}}", searchResults)
    .replace(/{{dateTime}}|{{currentDate}}/g, currentDate);
}

This function pulls live settings via getSettings(), then performs string replacement to inject the formatted results and timestamp. Any customizations made to the systemPrompt setting automatically flow through this interpolation chain.

Source: client/modules/systemPrompt.ts:8-17

Editing the Prompt Through the UI

Users can modify the system prompt without editing source files. The System Prompt editor resides in client/components/Pages/Main/Menu/AISettings/components/SystemPromptInput.tsx, which binds a <Textarea> component directly to the systemPrompt field:

• Custom prompts persist via settingsPubSub and override defaults immediately
• Restore default functionality calls handleRestoreDefaultInstructions() to revert to the template defined in defaultSettings

Source: SystemPromptInput.tsx:17-26

How Citations Are Generated

The bullet list that replaces {{searchResults}} is constructed by getFormattedSearchResults() in client/modules/textGenerationUtilities.ts:

export function getFormattedSearchResults(shouldIncludeUrl: boolean) {
  const searchResults = getLlmTextSearchResults();

  if (searchResults.length === 0) return "None.";

  if (shouldIncludeUrl) {
    return searchResults
      .map(([title, snippet, url]) => `• [${title}](${url}) | ${snippet}`)
      .join("\n");
  }

  return searchResults
    .map(([title, snippet]) => `• ${title} | ${snippet}`)
    .join("\n");
}

When shouldIncludeUrl is true (the default in the generation flow), each result renders as a markdown link [title](url) followed by the snippet. This formatted string becomes the value substituted for {{searchResults}} in the system prompt.

Source: textGenerationUtilities.ts:38-45

Customizing Citation Formatting

You have two entry points to modify citation appearance:

1. Edit the template description — Update defaultSettings.systemPrompt (or the UI field) to instruct the LLM on alternative citation styles (e.g., footnotes, author-date, or numbered references).

2. Override the formatter function — Modify getFormattedSearchResults() in client/modules/textGenerationUtilities.ts to output different markdown structures. For example, to extract domain-only citations:

.map(([title, snippet, url]) => {
  const domain = new URL(url).hostname.replace(/^www\./, '');
  return `• ${title} (${domain}) | ${snippet}`;
})

End-to-End Flow

1. User edits the prompt in AI Settings → updates persist via settingsPubSub
2. textGeneration.ts calls getFormattedSearchResults(true) to generate the markdown list
3. getSystemPrompt() substitutes {{searchResults}} and date placeholders
4. Final string populates the first chat message (ChatMessage.role === "user") sent to the LLM

Sources: textGeneration.ts:12-18 and textGenerationUtilities.ts:12-18

Complete Customization Examples

Changing the Default System Prompt

Modify client/modules/settings.ts to enforce footnote-style citations:

// client/modules/settings.ts
export const defaultSettings = {
  // …other settings,
  systemPrompt: `You are a concise assistant. Use the results below as your only source.
  
  // Custom citation rule (footnotes):
  Cite each fact with a footnote like [^1]. The footnote list will appear after the answer.
  
  Fetched on {{currentDate}}:
  
  {{searchResults}}`,
};

Adding a Custom Citation Formatter

Extend client/modules/textGenerationUtilities.ts to generate numbered footnotes:

// client/modules/textGenerationUtilities.ts
export function getFormattedSearchResults(shouldIncludeUrl: boolean) {
  const searchResults = getLlmTextSearchResults();

  if (searchResults.length === 0) return "None.";

  if (shouldIncludeUrl) {
    // New footnote style
    return searchResults
      .map(([title, snippet, url], idx) => {
        const footnote = `[^${idx + 1}]`;
        return `• ${title} ${footnote} | ${snippet}`;
      })
      .join("\n");
  }

  return searchResults
    .map(([title, snippet]) => `• ${title} | ${snippet}`)
    .join("\n");
}

Then append footnote definitions in client/modules/systemPrompt.ts:

// client/modules/systemPrompt.ts
export function getSystemPrompt(searchResults: string) {
  const currentDate = new Intl.DateTimeFormat("en-CA", {
    year: "numeric",
    month: "2-digit",
    day: "2-digit",
  }).format(new Date());

  const promptWithResults = getSettings()
    .systemPrompt.replace("{{searchResults}}", searchResults)
    .replace(/{{dateTime}}|{{currentDate}}/g, currentDate);
    
  const footnotes = getLlmTextSearchResults()
    .map(([, , url], idx) => `[^${idx + 1}]: ${url}`)
    .join("\n");
    
  return `${promptWithResults}\n\n${footnotes}`;
}

Summary

• Template location: The default system prompt lives in client/modules/settings.ts as defaultSettings.systemPrompt, supporting {{searchResults}} and {{currentDate}} placeholders.
• Runtime interpolation: getSystemPrompt() in client/modules/systemPrompt.ts performs placeholder substitution using live settings.
• UI editing: Users can modify prompts via SystemPromptInput.tsx, with changes persisting through settingsPubSub.
• Citation formatting: getFormattedSearchResults() in client/modules/textGenerationUtilities.ts controls how search results appear, defaulting to markdown bullet lists with linked titles.
• Customization paths: Change the template text to alter instructions, or modify the formatter function to change the actual citation markup structure.

Frequently Asked Questions

How do I reset the system prompt to default in MiniSearch?

Click the restore default button in the AI Settings UI, which triggers handleRestoreDefaultInstructions() in SystemPromptInput.tsx to reset the form value to defaultSettings.systemPrompt. This reverts any custom text to the original template defined in client/modules/settings.ts.

Can I use different date formats in the system prompt?

Yes. Modify the Intl.DateTimeFormat configuration in getSystemPrompt() within client/modules/systemPrompt.ts. The current implementation hardcodes "en-CA" with year: "numeric", month: "2-digit", and day: "2-digit", but you can change the locale or options to match regional requirements.

Where does MiniSearch inject the formatted prompt into the LLM request?

The assembled prompt is injected into the chat message array by client/modules/textGeneration.ts (lines 12-18) and client/modules/textGenerationUtilities.ts (lines 12-18). The system prompt becomes the first user message (ChatMessage.role === "user") sent to the language model, combining the template, current date, and formatted search results.

{
  "mcpServers": {
    "instagit": {
      "command": "npx",
      "args": ["-y", "instagit@latest"]
    }
  }
}