Simplify always-on skill prompt inclusion

Generated-By: PostHog Code
Task-Id: b0e948e2-b733-4d51-be6a-efd68d54216e

Author: adboio

packages/agent/src/server/agent-server.test.ts

@@ -2320,22 +2320,6 @@ describe("AgentServer HTTP Mode", () => {
       serverInternals.posthogAPI.downloadArtifact = downloadArtifact;
 
       const token = createToken();
-      const artifact = {
-        id: "skill-artifact-1",
-        name: "local-test-skill.zip",
-        type: "skill_bundle",
-        source: "posthog_code_skill",
-        storage_path: "tasks/artifacts/local-test-skill.zip",
-        content_type: "application/zip",
-        metadata: {
-          skill_name: "local-test-skill",
-          skill_source: "user",
-          content_sha256: checksum,
-          bundle_format: "zip",
-          schema_version: 1,
-          always_on: true,
-        },
-      };
       const response = await fetch(`http://localhost:${port}/command`, {
         method: "POST",
         headers: {
@@ -2348,7 +2332,23 @@ describe("AgentServer HTTP Mode", () => {
           method: "user_message",
           params: {
             content: "/local-test-skill with context",
-            artifacts: [artifact],
+            artifacts: [
+              {
+                id: "skill-artifact-1",
+                name: "local-test-skill.zip",
+                type: "skill_bundle",
+                source: "posthog_code_skill",
+                storage_path: "tasks/artifacts/local-test-skill.zip",
+                content_type: "application/zip",
+                metadata: {
+                  skill_name: "local-test-skill",
+                  skill_source: "user",
+                  content_sha256: checksum,
+                  bundle_format: "zip",
+                  schema_version: 1,
+                },
+              },
+            ],
           },
         }),
       });
@@ -2374,38 +2374,11 @@ describe("AgentServer HTTP Mode", () => {
 
       expect(sentText).toBe("/local-test-skill with context");
       expect(sentMeta?.localSkillContext).toContain(
-        "Always-on skills apply for the entire session",
-      );
-      expect(sentMeta?.localSkillContext).toContain(
-        "/skills/local-test-skill/SKILL.md",
-      );
-      expect(sentMeta?.localSkillContext).toContain(
-        "User request:\nwith context",
+        'local skill "/local-test-skill"',
       );
-      expect(sentMeta?.localSkillContext).not.toContain("LOCAL_SKILL_MARKER");
+      expect(sentMeta?.localSkillContext).toContain("LOCAL_SKILL_MARKER");
+      expect(sentMeta?.localSkillContext).toContain("with context");
       expect(sentMeta?.localSkillName).toBe("local-test-skill");
-
-      await fetch(`http://localhost:${port}/command`, {
-        method: "POST",
-        headers: {
-          Authorization: `Bearer ${token}`,
-          "Content-Type": "application/json",
-        },
-        body: JSON.stringify({
-          jsonrpc: "2.0",
-          id: "skill-followup",
-          method: "user_message",
-          params: {
-            content: "Follow up",
-            artifacts: [artifact],
-          },
-        }),
-      });
-
-      expect(prompt).toHaveBeenCalledTimes(2);
-      expect(
-        prompt.mock.calls[1]?.[0]._meta?.localSkillContext,
-      ).toBeUndefined();
     }, 20000);
 
     it("lists co-installed dependency skills with their paths in the skill context", async () => {

packages/agent/src/server/agent-server.ts

@@ -395,7 +395,6 @@ export class AgentServer {
   private warmAutoPublishResolved = false;
   private installedSkillBundles = new Set<string>();
   private installedSkillBundleInfo = new Map<string, InstalledSkillBundle>();
-  private alwaysOnSkillsActivatedSessionId: string | null = null;
   private installingSkillBundles = new Map<string, Promise<void>>();
   // Guards against concurrent session initialization. autoInitializeSession() and
   // the GET /events SSE handler can both call initializeSession() — the SSE connection
@@ -2839,44 +2838,8 @@ export class AgentServer {
     runId: string,
     artifacts: TaskRunArtifact[],
   ): LocalSkillPromptContext | null {
-    const alwaysOnSkills = artifacts
-      .filter(
-        (artifact) =>
-          artifact.type === "skill_bundle" &&
-          artifact.metadata?.always_on === true,
-      )
-      .sort((left, right) =>
-        `${left.metadata?.skill_source}:${left.metadata?.skill_name}`.localeCompare(
-          `${right.metadata?.skill_source}:${right.metadata?.skill_name}`,
-        ),
-      )
-      .map((artifact) =>
-        this.installedSkillBundleInfo.get(
-          this.getInstalledSkillBundleInfoKey(
-            runId,
-            artifact.metadata?.skill_name ?? "",
-          ),
-        ),
-      )
-      .filter((skill): skill is InstalledSkillBundle => !!skill);
-    const sessionId = this.session?.acpSessionId;
-    const shouldActivateAlwaysOnSkills =
-      alwaysOnSkills.length > 0 &&
-      !!sessionId &&
-      this.alwaysOnSkillsActivatedSessionId !== sessionId;
-    const alwaysOnContext = shouldActivateAlwaysOnSkills
-      ? [
-          "Always-on skills apply for the entire session. Before proceeding, read each SKILL.md below from the filesystem in the listed order and follow its instructions for the entire session.",
-          ...alwaysOnSkills.map(
-            (skill) => `- /${skill.skillName}: ${skill.skillRoot}/SKILL.md`,
-          ),
-        ].join("\n")
-      : null;
-    if (shouldActivateAlwaysOnSkills && sessionId) {
-      this.alwaysOnSkillsActivatedSessionId = sessionId;
-    }
     if (contentBlocks.length === 0) {
-      return alwaysOnContext ? { context: alwaysOnContext } : null;
+      return null;
     }
 
     const textBlockIndex = contentBlocks.findIndex(
@@ -2891,23 +2854,6 @@ export class AgentServer {
         : null;
 
     if (invocation) {
-      const invokedAlwaysOnSkill = alwaysOnSkills.find(
-        (skill) => skill.skillName === invocation.skillName,
-      );
-      if (invokedAlwaysOnSkill) {
-        const invokedContext = this.buildInstalledSkillPrompt(
-          invokedAlwaysOnSkill,
-          invocation.args,
-          this.getCoInstalledSkillBundles(runId, invocation.skillName),
-          false,
-        );
-        return {
-          skillName: invocation.skillName,
-          context: alwaysOnContext
-            ? `${alwaysOnContext}\n\n${invokedContext}`
-            : invokedContext,
-        };
-      }
       const hasMatchingArtifact = artifacts.some(
         (artifact) =>
           artifact.type === "skill_bundle" &&
@@ -2919,16 +2865,13 @@ export class AgentServer {
           )
         : undefined;
       if (installedSkill) {
-        const invokedContext = this.buildInstalledSkillPrompt(
-          installedSkill,
-          invocation.args,
-          this.getCoInstalledSkillBundles(runId, invocation.skillName),
-        );
         return {
           skillName: invocation.skillName,
-          context: alwaysOnContext
-            ? `${alwaysOnContext}\n\n${invokedContext}`
-            : invokedContext,
+          context: this.buildInstalledSkillPrompt(
+            installedSkill,
+            invocation.args,
+            this.getCoInstalledSkillBundles(runId, invocation.skillName),
+          ),
         };
       }
     }
@@ -2940,17 +2883,7 @@ export class AgentServer {
       )
       .map((block) => block.text)
       .join("\n");
-    const attachedContext = this.buildAttachedSkillsPromptContext(
-      runId,
-      artifacts.filter((artifact) => artifact.metadata?.always_on !== true),
-      messageText,
-    );
-    if (!alwaysOnContext) return attachedContext;
-    return {
-      context: attachedContext
-        ? `${alwaysOnContext}\n\n${attachedContext.context}`
-        : alwaysOnContext,
-    };
+    return this.buildAttachedSkillsPromptContext(runId, artifacts, messageText);
   }
 
   /**
@@ -3049,19 +2982,14 @@ export class AgentServer {
     skill: InstalledSkillBundle,
     args: string | undefined,
     coInstalledSkills: InstalledSkillBundle[] = [],
-    includeDefinition = true,
   ): string {
     return [
       `The user invoked the local skill "/${skill.skillName}". Apply these skill instructions for this turn.`,
       "",
-      ...(includeDefinition
-        ? [
-            `--- BEGIN LOCAL SKILL ${skill.skillName} ---`,
-            skill.skillDefinition.trim(),
-            `--- END LOCAL SKILL ${skill.skillName} ---`,
-            "",
-          ]
-        : []),
+      `--- BEGIN LOCAL SKILL ${skill.skillName} ---`,
+      skill.skillDefinition.trim(),
+      `--- END LOCAL SKILL ${skill.skillName} ---`,
+      "",
       `Installed skill path: ${skill.skillRoot}`,
       ...(coInstalledSkills.length > 0
         ? [

packages/core/src/sessions/cloudArtifactIdentifiers.ts

@@ -51,7 +51,6 @@ export interface CloudSkillBundleRef {
   name: string;
   source: UploadableSkillSource;
   path: string;
-  alwaysOn?: boolean;
 }
 
 export interface LocalSkillBundle {

packages/core/src/sessions/cloudArtifactService.test.ts

@@ -170,7 +170,6 @@ describe("CloudArtifactService", () => {
           name: "local-skill",
           source: "user",
           path: "/tmp/local-skill",
-          alwaysOn: true,
         },
       ],
     );
@@ -189,57 +188,13 @@ describe("CloudArtifactService", () => {
             skill_source: "user",
             bundle_format: "zip",
             schema_version: 1,
-            always_on: true,
           }),
         }),
       ],
     );
     fetchMock.mockRestore();
   });
 
-  it("skips an unavailable always-on skill without failing the upload", async () => {
-    const service = new CloudArtifactService(
-      vi.fn(),
-      vi.fn().mockRejectedValue(new Error("missing skill")),
-      passthroughDeps,
-    );
-
-    await expect(
-      service.uploadRunAttachments(
-        makeClient(),
-        "task-1",
-        "run-1",
-        [],
-        [
-          {
-            name: "missing",
-            source: "user",
-            path: "/tmp/missing",
-            alwaysOn: true,
-          },
-        ],
-      ),
-    ).resolves.toEqual([]);
-  });
-
-  it("fails when an explicitly requested skill is unavailable", async () => {
-    const service = new CloudArtifactService(
-      vi.fn(),
-      vi.fn().mockRejectedValue(new Error("missing skill")),
-      passthroughDeps,
-    );
-
-    await expect(
-      service.uploadRunAttachments(
-        makeClient(),
-        "task-1",
-        "run-1",
-        [],
-        [{ name: "missing", source: "user", path: "/tmp/missing" }],
-      ),
-    ).rejects.toThrow("missing skill");
-  });
-
   it("uploads dependency skills the resolver adds to a tagged skill", async () => {
     const fetchMock = vi
       .spyOn(globalThis, "fetch")

packages/core/src/sessions/cloudArtifactService.ts

@@ -173,7 +173,6 @@ export class CloudArtifactService {
       ...(await this.loadCloudAttachments(filePaths)),
       ...(await this.loadCloudSkillBundles(skillBundles)),
     ];
-    if (attachments.length === 0) return [];
     const preparedArtifacts = await client.prepareTaskRunArtifactUploads(
       taskId,
       runId,
@@ -233,30 +232,8 @@ export class CloudArtifactService {
     if (skillBundleRefs.length === 0) {
       return [];
     }
-    const explicitRefs = skillBundleRefs.filter((ref) => !ref.alwaysOn);
-    const alwaysOnRefs = skillBundleRefs.filter((ref) => ref.alwaysOn);
-    const explicit = await this.loadCloudSkillBundleRefs(explicitRefs);
-    const alwaysOn = (
-      await Promise.all(
-        alwaysOnRefs.map((ref) =>
-          this.loadCloudSkillBundleRefs([ref]).catch(() => []),
-        ),
-      )
-    ).flat();
-    const deduplicated = new Map(
-      [...explicit, ...alwaysOn].map((attachment) => [
-        attachment.filePath,
-        attachment,
-      ]),
-    );
-    return [...deduplicated.values()];
-  }
-
-  private async loadCloudSkillBundleRefs(
-    refs: CloudSkillBundleRef[],
-  ): Promise<LoadedCloudAttachment[]> {
-    if (refs.length === 0) return [];
-    const expandedRefs = await this.resolveSkillBundleDependencies(refs);
+    const expandedRefs =
+      await this.resolveSkillBundleDependencies(skillBundleRefs);
     return Promise.all(
       expandedRefs.map(async (skillBundleRef) => {
         const bundle = await this.bundleLocalSkill(skillBundleRef);
@@ -287,7 +264,6 @@ export class CloudArtifactService {
               content_sha256: bundle.contentSha256,
               bundle_format: "zip",
               schema_version: 1,
-              ...(skillBundleRef.alwaysOn ? { always_on: true } : {}),
             },
           },
         };