feat: Adds in prompt.yml support

Author: maraisr

examples/ai/generate-text.ts

@@ -2,18 +2,14 @@ import {githubModels} from '@github/models'
 import {generateText} from 'ai'
 import 'dotenv/config'
 
-async function main() {
-  const result = await generateText({
-    model: githubModels('openai/gpt-4o'),
-    prompt: 'I want 100 words on how to inflate a balloon.',
-  })
+const result = await generateText({
+  model: githubModels('openai/gpt-4o'),
+  prompt: 'I want 100 words on how to inflate a balloon.',
+})
 
-  console.log('Text:')
-  console.log(result.text)
-  console.log()
+console.log('Text:')
+console.log(result.text)
+console.log()
 
-  console.log('Token usage:', result.usage)
-  console.log('Finish reason:', result.finishReason)
-}
-
-main().catch(console.error)
+console.log('Token usage:', result.usage)
+console.log('Finish reason:', result.finishReason)

examples/ai/prompt.ts

@@ -0,0 +1,21 @@
+import {readFile} from 'node:fs/promises'
+import {parseYAML} from 'confbox/yaml'
+import {createObjectPrompt} from '@github/models/prompt'
+import {generateObject} from 'ai'
+import 'dotenv/config'
+
+const promptFile = parseYAML(await readFile('./teacher.prompt.yml', 'utf8'))
+const prompt = createObjectPrompt(promptFile)
+
+const result = await generateObject(
+  prompt({
+    subject: 'balloon popping',
+  }),
+)
+
+console.log('Object:')
+console.log(result.object)
+console.log()
+
+console.log('Token usage:', result.usage)
+console.log('Finish reason:', result.finishReason)

examples/ai/teacher.prompt.yml

@@ -0,0 +1,26 @@
+name: teacher
+model: openai/gpt-4.1
+responseFormat: json_schema
+jsonSchema: |-
+  {
+    "name": "explanation",
+    "strict": true,
+    "schema": {
+      "type": "object",
+      "properties": {
+        "lesson": {
+          "type": "string",
+          "description": "The lesson about the subject"
+        }
+      },
+      "additionalProperties": false,
+      "required": [
+        "lesson"
+      ]
+    }
+  }
+messages:
+  - role: system
+    content: You're an elementary school teacher who loves to make learning fun.
+  - role: user
+    content: Please explain {{subject}} in as little as 5 sentences and give it to be as json.

package-lock.json

@@ -14,6 +14,10 @@
       "types": "./dist/index.d.ts",
       "default": "./dist/index.js"
     },
+    "./prompt": {
+      "types": "./dist/prompt.d.ts",
+      "default": "./dist/prompt.js"
+    },
     "./package.json": "./package.json"
   },
   "scripts": {
@@ -39,19 +43,22 @@
   "dependencies": {
     "@ai-sdk/openai-compatible": "beta",
     "@ai-sdk/provider": "beta",
-    "@ai-sdk/provider-utils": "beta"
+    "@ai-sdk/provider-utils": "beta",
+    "templite": "^1.2.0",
+    "tiny-invariant": "^1.3.3",
+    "zod": "^3 || ^4"
   },
   "devDependencies": {
     "@github/prettier-config": "0.0.6",
     "@types/node": "^24",
+    "dotenv": "^17.2.0",
     "eslint": "^9",
     "eslint-plugin-github": "^6",
     "eslint-plugin-simple-import-sort": "12.1.1",
     "prettier": "^3",
     "tsup": "^8.3.0",
     "typescript": "^5.7.2",
-    "vitest": "^3",
-    "dotenv": "^17.2.0"
+    "vitest": "^3"
   },
   "engines": {
     "node": ">=20"

package.json

@@ -0,0 +1,117 @@
+import type {ProviderV2} from '@ai-sdk/provider'
+import {jsonSchema} from '@ai-sdk/provider-utils'
+import templite from 'templite'
+import invariant from 'tiny-invariant'
+import {z} from 'zod/v4'
+
+import {githubModels} from './provider'
+
+type Variables = Record<string, string | number | boolean>
+
+export function crateTextPrompt(config: unknown, provider?: ProviderV2) {
+  const p = schema.parse(config)
+  if (p.responseFormat) invariant(p.responseFormat === 'text', 'responseFormat must be "text" to generate text')
+
+  provider ||= githubModels
+
+  const model = provider.languageModel(p.model)
+
+  return <V extends Variables>(variables: V) => {
+    return {
+      model,
+      messages: messages(p, variables),
+      ...settings(p),
+    } as const
+  }
+}
+
+export function createObjectPrompt(config: unknown, provider?: ProviderV2) {
+  const p = schema.parse(config)
+  invariant(
+    p.responseFormat === 'json_object' || p.responseFormat === 'json_schema',
+    'responseFormat must be either "json_object" or "json_schema" to generate objects',
+  )
+
+  provider ||= githubModels
+  const model = provider.languageModel(p.model)
+
+  let schemaProperties = {}
+  if (p.responseFormat === 'json_schema' && p.jsonSchema) {
+    const jSchema = JSON.parse(p.jsonSchema)
+    schemaProperties = {
+      output: undefined,
+      schema: jsonSchema(jSchema.schema),
+      schemaName: jSchema.name,
+      schemaDescription: jSchema.description,
+    }
+  }
+
+  return <V extends Variables>(variables: V) => {
+    return {
+      model,
+      messages: messages(p, variables),
+      output: 'no-schema',
+      ...schemaProperties,
+      ...settings(p),
+    } as const
+  }
+}
+
+// ---
+
+function messages<V extends Variables>(config: Schema, variables: V) {
+  const msgs = [] as Message[]
+  for (const msg of config.messages) {
+    msgs.push({
+      role: msg.role,
+      content: templite(msg.content, variables),
+    })
+  }
+  return msgs
+}
+
+function settings(config: Schema) {
+  return {
+    maxOutputTokens: config.modelParameters?.maxTokens,
+    temperature: config.modelParameters?.temperature,
+    topP: config.modelParameters?.topP,
+  } as const
+}
+
+const message = z.discriminatedUnion('role', [
+  z.object({role: z.literal('user'), content: z.string()}),
+  z.object({role: z.literal('system'), content: z.string()}),
+])
+
+type Message = z.infer<typeof message>
+
+const schema = z
+  .object({
+    name: z.string().optional(),
+    description: z.string().optional(),
+    model: z.string(),
+    modelParameters: z
+      .object({
+        maxTokens: z.number().positive().optional(),
+        temperature: z.number().min(0).max(1).optional(),
+        topP: z.number().min(0).max(1).optional(),
+      })
+      .optional(),
+    messages: z.array(message),
+    responseFormat: z.enum(['text', 'json_object', 'json_schema']).optional(),
+    jsonSchema: z.string().optional(),
+  })
+  .refine(
+    data => {
+      if (data.responseFormat === 'json_schema') {
+        return data.jsonSchema !== undefined
+      }
+      return true
+    },
+    {
+      message: "jsonSchema must be provided when responseFormat is 'json_schema'",
+      path: ['jsonSchema'],
+    },
+  )
+
+type Schema = z.infer<typeof schema>

src/prompt.ts

@@ -66,6 +66,7 @@ export function createGitHubModels(options: GitHubModelsProviderOptions = {}): G
     headers: getHeaders,
     fetch: options.fetch,
     includeUsage: true,
+    supportsStructuredOutputs: true,
   } satisfies OpenAICompatibleChatConfig
 
   const createModel = (modelId: GitHubModelsChatModelId) => new OpenAICompatibleChatLanguageModel(modelId, baseOptions)

src/provider.ts

@@ -4,6 +4,7 @@ export default defineConfig([
   {
     entry: {
       index: 'src/index.ts',
+      prompt: 'src/prompt.ts',
     },
     format: ['esm'],
     dts: true,