feat(tess): add configurable Pi interaction service (#728)

packages/mosaic/src/fleet/interaction-service-profile.ts

@@ -0,0 +1,110 @@
+import { readFile } from 'node:fs/promises';
+import YAML from 'yaml';
+import type { FleetAgent } from '../commands/fleet.js';
+
+const REQUIRED_RUNTIME = 'pi';
+const REQUIRED_MODEL = 'openai/gpt-5.6-sol';
+const REQUIRED_REASONING = 'high';
+const REQUIRED_TOOL_POLICY = 'operator-interaction';
+const AGENT_NAME_PATTERN = /^[A-Za-z0-9_.-]+$/;
+
+export interface InteractionServiceProfile {
+  runtime: string;
+  model: string;
+  reasoning: string;
+  toolPolicy: string;
+}
+
+export interface EffectiveInteractionPolicy {
+  agentName: string;
+  runtime: string;
+  model: string;
+  reasoning: string;
+  toolPolicy: string;
+}
+
+export class InteractionServiceProfileError extends Error {
+  constructor(
+    readonly code: 'invalid_profile' | 'invalid_request',
+    message: string,
+  ) {
+    super(message);
+    this.name = InteractionServiceProfileError.name;
+  }
+}
+
+export async function readInteractionServiceProfile(
+  path: string,
+  overrides: Partial<InteractionServiceProfile> = {},
+): Promise<InteractionServiceProfile> {
+  const parsed: unknown = YAML.parse(await readFile(path, 'utf8'));
+  if (!isRecord(parsed)) {
+    throw new InteractionServiceProfileError(
+      'invalid_profile',
+      'Service profile must be an object',
+    );
+  }
+  const profile: InteractionServiceProfile = {
+    runtime: valueOrUndefined(overrides.runtime, parsed['runtime']),
+    model: valueOrUndefined(overrides.model, parsed['model']),
+    reasoning: valueOrUndefined(overrides.reasoning, parsed['reasoning']),
+    toolPolicy: valueOrUndefined(overrides.toolPolicy, parsed['tool_policy']),
+  };
+  assertPinnedPolicy(profile);
+  return profile;
+}
+
+export function provisionInteractionService(
+  profile: InteractionServiceProfile,
+  input: { agentName: string },
+): { rosterAgent: FleetAgent; effectivePolicy: EffectiveInteractionPolicy } {
+  assertPinnedPolicy(profile);
+  if (!AGENT_NAME_PATTERN.test(input.agentName)) {
+    throw new InteractionServiceProfileError(
+      'invalid_request',
+      'Agent name must contain only letters, numbers, dots, underscores, or hyphens',
+    );
+  }
+  const effectivePolicy: EffectiveInteractionPolicy = {
+    agentName: input.agentName,
+    runtime: profile.runtime,
+    model: profile.model,
+    reasoning: profile.reasoning,
+    toolPolicy: profile.toolPolicy,
+  };
+  return {
+    rosterAgent: {
+      name: input.agentName,
+      runtime: profile.runtime,
+      className: profile.toolPolicy,
+      modelHint: profile.model,
+      reasoningLevel: profile.reasoning,
+      toolPolicy: profile.toolPolicy,
+      persistentPersona: true,
+    },
+    effectivePolicy,
+  };
+}
+
+function assertPinnedPolicy(profile: InteractionServiceProfile): void {
+  const invalid =
+    profile.runtime !== REQUIRED_RUNTIME ||
+    profile.model !== REQUIRED_MODEL ||
+    profile.reasoning !== REQUIRED_REASONING ||
+    profile.toolPolicy !== REQUIRED_TOOL_POLICY;
+  if (invalid) {
+    throw new InteractionServiceProfileError(
+      'invalid_profile',
+      `Service profile must pin ${REQUIRED_RUNTIME}, ${REQUIRED_MODEL}, ${REQUIRED_REASONING}, and ${REQUIRED_TOOL_POLICY}`,
+    );
+  }
+}
+
+function valueOrUndefined(override: string | undefined, value: unknown): string {
+  if (override !== undefined) return override;
+  return typeof value === 'string' ? value : '';
+}
+
+function isRecord(value: unknown): value is Record<string, unknown> {
+  return typeof value === 'object' && value !== null && !Array.isArray(value);
+}