Partials

A partial is a named, reusable instruction fragment. Skills are stored in a global registry and can be embedded into any agent's system prompt using the {{partial:name}} placeholder.

Functions

loadPartialsFrom(dir)

async function loadPartialsFrom(dir: string): Promise<PromptPartial[]>

Read every .md file in dir, parse each one as a partial, register it, and return the list. Call this before loading any agents that reference partials.

await loadPartialsFrom('./skills');

---

loadSkill(filePath)

async function loadSkill(filePath: string): Promise<Skill>

Load a single partial file and register it.

---

parsePartial(content)

function parsePartial(content: string): Skill

Parse a partial from a markdown string. Does not register it — call registerPartial if you want it in the registry.

const skill = parsePartial(`
---
name: tone
description: Sets the response tone
---
Always respond in a clear, professional tone.
`);

---

registerPartial(name, skill)

function registerPartial(name: string, skill: Skill): void

Register a partial manually. Useful when generating partials programmatically or in tests.

---

getPartial(name) / hasPartial(name) / listPartials() / clearPartials()

function getPartial(name: string): Skill      // throws if not found
function hasPartial(name: string): boolean
function listPartials(): string[]
function clearPartials(): void

Standard registry utilities. clearPartials() is useful in tests to reset state between cases.

---

PromptPartial

interface PromptPartial {
  name: string;
  description?: string;
  instructions: string;
}

---

Markdown format

---
name: citation-style
description: How to cite sources in responses
---
When citing sources, use the format: [Source: <title>, <url>].
Always cite at least one source per factual claim.

Field	Required	Description
name	Yes	Registry key. Used in {{partial:name}} placeholders.
description	No	Human-readable description of the skill's purpose.
Body	Yes	The instruction text injected at the placeholder site.

---

Using partials in agents

Reference a registered partial anywhere in an agent's instruction body:

---
name: researcher
model: anthropic/claude-3-5-sonnet
---
You are a research specialist.

{{partial:tone}}
{{partial:citation-style}}

Focus on primary sources when possible.

The placeholder is replaced with the skill's full instruction text when the agent is loaded.

---

Example

import {
  loadPartialsFrom,
  loadAgentsFrom,
  getAgent,
  configure,
  anthropic,
  WebFetch,
} from '@daedalus-ai-dev/ai-sdk';

configure({ provider: anthropic('claude-3-5-sonnet-20241022') });

// Partials must be registered before agents that reference them
await loadPartialsFrom('./skills');
await loadAgentsFrom('./agents', { tools: { 'web-fetch': new WebFetch() } });

const response = await getAgent('researcher').prompt('Latest news on fusion energy?');
console.log(response.text);

In tests

import { registerPartial, clearPartials, parseAgent } from '@daedalus-ai-dev/ai-sdk';
import { beforeEach } from 'vitest';

beforeEach(() => clearPartials());

test('agent uses partial instructions', () => {
  registerPartial('tone', { name: 'tone', instructions: 'Be concise.' });

  const runner = parseAgent(`
---
name: assistant
---
Help the user. {{partial:tone}}
  `);

  expect(runner).toBeDefined();
});