diff --git a/CHANGELOG.md b/CHANGELOG.md
index 40849d9d..dc293bf7 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,16 @@
 # Changelog
 
+## 2026-09-02
+
+### Changes
+
+- Prima: The three envelope builders (`pw`/`do`/`go`, failures, and `check`/`ask`/`verify`/`research`)
+  now share one tail builder instead of each repeating the instance/status/artifacts block. Artifact
+  paths flow back from the write as a return value rather than through a mutable field that had to be
+  read in the right order, so an envelope can no longer come back missing its Artifacts section.
+  Per-step file names (`aria.yaml`/`html`/`diff.yaml`) written during a `do` run now have a single
+  owner shared with the doc line the envelope advertises, so the two can no longer drift apart.
+
 ## 2026-09-01
 
 ### Changes
diff --git a/boat/prima/src/cli.ts b/boat/prima/src/cli.ts
index bac3fbb6..8243aa0d 100644
--- a/boat/prima/src/cli.ts
+++ b/boat/prima/src/cli.ts
@@ -129,7 +129,8 @@ function primaFor(options: any): Prima {
   return new Prima(buildOptions(options));
 }
 
-async function runPrima(options: any, command: string, run: (prima: Prima) => Promise<EnvelopeData>): Promise<void> {
+async function runPrima(options: any, command: string, run: (prima: Prima) => Promise<EnvelopeData>, opts: { browser?: boolean; record?: boolean } = {}): Promise<void> {
+  const { browser = true, record = true } = opts;
   setQuietMode(!isVerboseMode());
   trackActivityLine();
   const prima = primaFor(options);
@@ -137,13 +138,13 @@ async function runPrima(options: any, command: string, run: (prima: Prima) => Pr
 
   let envelope: EnvelopeData;
   try {
-    await prima.start();
+    if (browser) await prima.start();
     envelope = await run(prima);
   } catch (error) {
     envelope = await prima.toolFailureEnvelope(command, error);
   }
 
-  prima.record(envelope, Date.now() - startedAt);
+  if (record) prima.record(envelope, Date.now() - startedAt);
   clearActivityLine();
   console.log(renderEnvelope(envelope));
   await prima.stop().catch(() => {});
@@ -221,11 +222,7 @@ export function createPrimaCommands(name = 'prima'): Command {
   addCommonOptions(cmd.command('status <hash>').description('Show the artifacts and page detail recorded for an earlier command'))
     .addHelpText('after', `\n${statusHelp}`)
     .action(async (hash, options) => {
-      setQuietMode(!isVerboseMode());
-      const prima = primaFor(options);
-      const envelope = await prima.status(hash).catch((error: unknown) => prima.toolFailureEnvelope(`status ${hash}`, error));
-      console.log(renderEnvelope(envelope));
-      process.exit(envelope.ok ? 0 : 1);
+      await runPrima(options, `status ${hash}`, (prima) => prima.status(hash), { browser: false, record: false });
     });
 
   addCommonOptions(cmd.command('report').description('Turn every command of a session into one html and markdown report'))
diff --git a/boat/prima/src/envelope.ts b/boat/prima/src/envelope.ts
index c1e6d477..9250f310 100644
--- a/boat/prima/src/envelope.ts
+++ b/boat/prima/src/envelope.ts
@@ -5,6 +5,8 @@ export const STATUS_FILE = 'status.json';
 
 const ARTIFACT_FILES = { aria: 'aria.yml', html: 'page.html', screenshot: 'page.png', network: 'network.jsonl' };
 
+export const STEP_FILES = { aria: 'aria.yaml', html: 'html', diff: 'diff.yaml' };
+
 const EXPECTATION_LABELS = {
   passed: 'PASSED       ',
   failed: 'FAILED       ',
@@ -117,7 +119,7 @@ function renderSteps(data: EnvelopeData): string | null {
     lines.push(`${index + 1}. ${mark} ${step.label}`);
     for (const line of (step.proof || '').split('\n').filter(Boolean)) lines.push(`      ${line}`);
   });
-  if (data.stepFiles) lines.push('', `page after each step: ${data.stepFiles}/<n>-<step>.{aria.yaml,html,diff.yaml}`);
+  if (data.stepFiles) lines.push('', `page after each step: ${data.stepFiles}/<n>-<step>.{${Object.values(STEP_FILES).join(',')}}`);
   return section('Steps', lines.join('\n'));
 }
 
diff --git a/boat/prima/src/prima.ts b/boat/prima/src/prima.ts
index c5cfdbd4..0bb95a71 100644
--- a/boat/prima/src/prima.ts
+++ b/boat/prima/src/prima.ts
@@ -25,7 +25,7 @@ import { browserErrorMessage } from '../../../src/utils/browser-errors.ts';
 import { pluralize } from '../../../src/utils/logger.ts';
 import { mdq } from '../../../src/utils/markdown-query.ts';
 import { safeFilename } from '../../../src/utils/strings.ts';
-import { type EnvelopeData, type InstanceInfo, STATUS_FILE, readArtifacts, writeArtifacts } from './envelope.ts';
+import { type ArtifactPaths, type EnvelopeData, type InstanceInfo, STATUS_FILE, STEP_FILES, readArtifacts, writeArtifacts } from './envelope.ts';
 import { isFunctionExpression, takePwValue, toCodeceptWrapper } from './pw-parser.ts';
 import { type PwServerDescriptor, readDescriptors, selectDescriptor } from './pw-registry.ts';
 import { type SessionRun, latestSessionFile, readSession, recordCommand, sessionFile, sessionsDir } from './session-log.ts';
@@ -74,7 +74,6 @@ export class Prima {
   private server: { close: () => Promise<void> } | null = null;
   private attached: string | null = null;
   private session: SessionRun | null = null;
-  private artifacts?: EnvelopeData['artifacts'];
 
   constructor(options: PrimaOptions = {}) {
     this.options = options;
@@ -982,16 +981,13 @@ export class Prima {
 
   private async successEnvelope(command: string, used: string[], result: ActionResult, previousState: WebPageState | null): Promise<EnvelopeData> {
     const changes = await this.pageChanges(result, previousState, used[0]);
-    const status = await this.saveStatus(result);
     return {
       ok: true,
       command,
       used,
       page: this.pageBlock(result, previousState),
       changes,
-      instance: await this.instanceInfo(),
-      status,
-      artifacts: this.artifacts,
+      ...(await this.envelopeTail(result)),
     };
   }
 
@@ -1000,31 +996,30 @@ export class Prima {
     const failure: EnvelopeData['failure'] = { error: browserErrorMessage(error) };
     if (result.ariaSnapshot) failure.compactAria = compactAriaSnapshot(result.ariaSnapshot, true);
 
-    const status = await this.saveStatus(result);
     return {
       ok: false,
       command,
       page: this.pageBlock(result, previousState),
       failure,
-      instance: await this.instanceInfo(),
-      status,
-      artifacts: this.artifacts,
+      ...(await this.envelopeTail(result)),
     };
   }
 
   private async reportEnvelope(command: string, result: ActionResult, previousState: WebPageState | null, outcome: Partial<EnvelopeData>): Promise<EnvelopeData> {
-    const status = await this.saveStatus(result);
     return {
       ok: true,
       command,
       page: this.pageBlock(result, previousState),
       ...outcome,
-      instance: await this.instanceInfo(),
-      status,
-      artifacts: this.artifacts,
+      ...(await this.envelopeTail(result)),
     };
   }
 
+  private async envelopeTail(result: ActionResult): Promise<Pick<EnvelopeData, 'instance' | 'status' | 'artifacts'>> {
+    const { hash, artifacts } = await this.saveStatus(result);
+    return { instance: await this.instanceInfo(), status: hash, artifacts };
+  }
+
   private async capturedResult(previousState: WebPageState | null, opts: { screenshot?: boolean } = {}): Promise<ActionResult> {
     const captured = await this.bot
       .getExplorer()
@@ -1087,11 +1082,11 @@ export class Prima {
     };
   }
 
-  private async saveStatus(result: ActionResult): Promise<string> {
+  private async saveStatus(result: ActionResult): Promise<{ hash: string; artifacts: ArtifactPaths }> {
     const hash = this.statusHash();
-    await this.writeSnapshot(result);
+    const artifacts = await this.writeSnapshot(result);
     writeFileSync(path.join(this.statusDir(hash), STATUS_FILE), JSON.stringify({ page: this.pageBlock(result, null) }), 'utf-8');
-    return hash;
+    return { hash, artifacts };
   }
 
   private async writeStepFiles(index: number, label: string, diff: string): Promise<void> {
@@ -1103,17 +1098,17 @@ export class Prima {
     const stem = path.join(dir, `${index}-${safeFilename(label.slice(0, 60))}`);
     const result = ActionResult.fromState(state);
 
-    writeFileSync(`${stem}.aria.yaml`, result.ariaSnapshot ?? '', 'utf-8');
-    writeFileSync(`${stem}.html`, await result.combinedHtml(), 'utf-8');
-    if (diff) writeFileSync(`${stem}.diff.yaml`, diff, 'utf-8');
+    writeFileSync(`${stem}.${STEP_FILES.aria}`, result.ariaSnapshot ?? '', 'utf-8');
+    writeFileSync(`${stem}.${STEP_FILES.html}`, await result.combinedHtml(), 'utf-8');
+    if (diff) writeFileSync(`${stem}.${STEP_FILES.diff}`, diff, 'utf-8');
   }
 
-  private async writeSnapshot(result: ActionResult): Promise<void> {
-    this.artifacts = writeArtifacts(this.statusDir(), {
+  private async writeSnapshot(result: ActionResult): Promise<ArtifactPaths> {
+    return writeArtifacts(this.statusDir(), {
       aria: result.ariaSnapshot,
       html: await result.combinedHtml(),
       screenshot: result.screenshot,
-      requests: this.bot.requestStore().getRequests(),
+      requests: this.bot.requestStore().getMadeRequests(),
     });
   }
 
diff --git a/boat/prima/tests/envelope.test.ts b/boat/prima/tests/envelope.test.ts
index c2ae6532..2d400f5a 100644
--- a/boat/prima/tests/envelope.test.ts
+++ b/boat/prima/tests/envelope.test.ts
@@ -2,7 +2,7 @@ import { describe, expect, test } from 'bun:test';
 import { mkdtempSync, readFileSync, rmSync, writeFileSync } from 'node:fs';
 import { tmpdir } from 'node:os';
 import path from 'node:path';
-import { type EnvelopeData, readArtifacts, renderEnvelope, writeArtifacts } from '../src/envelope.ts';
+import { type EnvelopeData, STEP_FILES, readArtifacts, renderEnvelope, writeArtifacts } from '../src/envelope.ts';
 
 const base: EnvelopeData = {
   ok: true,
@@ -180,6 +180,12 @@ describe('renderEnvelope', () => {
     expect(out).toContain('page after each step: /tmp/x/<n>-<step>.{aria.yaml,html,diff.yaml}');
   });
 
+  test('the advertised step-file line names every STEP_FILES extension', () => {
+    const out = renderEnvelope({ ...base, steps: [{ label: "I.click('Add')", ok: true, proof: '' }], stepFiles: '/tmp/x' });
+    const line = out.split('\n').find((entry) => entry.includes('page after each step'))!;
+    for (const extension of Object.values(STEP_FILES)) expect(line).toContain(extension);
+  });
+
   test('open tabs alone are evidence enough for a running browser', () => {
     const out = renderEnvelope({ ...base, instance: { name: 'default', tabs: 2, others: [] } });
     expect(out).toContain('| running');
diff --git a/boat/prima/tests/prima.test.ts b/boat/prima/tests/prima.test.ts
index b2087d89..f16f3edd 100644
--- a/boat/prima/tests/prima.test.ts
+++ b/boat/prima/tests/prima.test.ts
@@ -95,7 +95,7 @@ function fakePrima(options: Record<string, unknown> = {}) {
     }),
     getCurrentState: () => fakeState(),
     getConfig: () => ({}),
-    requestStore: () => ({ getRequests: () => [] }),
+    requestStore: () => ({ getMadeRequests: () => [] }),
     getProvider: () => ({ chat: async () => '' }),
   };
   (prima as any).artifactsDir = artifactsRoot;