feat(eve): batch model calls within workflow steps by AndrewBarba · Pull Request #3034 · vercel/eve

AndrewBarba · 2026-09-04T14:15:27Z

Summary

eve currently checkpoints after every model call, even when a turn immediately continues through another tool call. That preserves maximum durability, but it also pays workflow orchestration overhead on every hop.

This adds the opt-in experimental.maxModelCallsPerWorkflowStep agent option, which runs up to N consecutive continuation calls inside one workflow step. The default remains 1. Batching stops before pending authorization, input, or coordination, when background work is scheduled, or when the turn naturally completes. Opted-in agents trade finer-grained replay checkpoints for lower orchestration overhead: replay restarts the current batch from its preceding checkpoint.

The change includes compiler and manifest validation, runtime propagation, unit and integration coverage, a deterministic e2e fixture eval, user-facing documentation, a concise research plan, and a patch changeset. Related to #876.

Validation

pnpm --filter eve exec vitest run --config vitest.unit.config.ts — 7,997 passed, 1 skipped
pnpm --filter eve exec vitest run --config vitest.integration.config.ts — 715 passed
pnpm typecheck
pnpm --filter eve build
pnpm docs:check
node ./scripts/guard-invariants.mjs
node_modules/.bin/oxlint --fix
git diff --check origin/main...HEAD
E2E evals are CI-only; the agent-tools fixture eval was updated and its fixture is covered by workspace typechecking.

Checklist

This change was requested or approved by a maintainer
I ran the relevant checks from CONTRIBUTING.md
I added tests and documentation where relevant
I added a changeset if this touches the published eve package
DCO sign-off passes for every commit (git commit --signoff)

Signed-off-by: Andrew Barba <barba@hey.com>

vercel · 2026-09-04T14:15:32Z

The latest updates on your projects. Learn more about Vercel for GitHub.

Project	Deployment	Actions	Updated
eve-docs	Ready	Preview, v0	Sep 4, 2026 2:17pm UTC
eve-docs-4759	Ready	Preview, v0	Sep 4, 2026 2:17pm UTC
eve-pkg	Ready	Preview, v0	Sep 4, 2026 2:17pm UTC

github-actions · 2026-09-04T14:19:07Z

Bundle + Package Summary: `apps/fixtures/weather-agent`

Key takeaways

No notable deltas vs main (abc130e).

Delta vs `main (abc130e)`

Area	Metric	Baseline	Current	Delta
Package	Packed tarball	8.64 MB	8.64 MB	+207 B ⚠️
Package	Unpacked publish size	32.53 MB	32.53 MB	+4.0 kB ⚠️
Package	Installed footprint	77.69 MB	77.70 MB	+4.0 kB ⚠️
Package	Published files	3821	3823	+2
Package	Installed files	7667	7669	+2
Package	Installed package instances	35	35	0
Package	Distinct installed package names	34	34	0
Package	Installed dependency edges	53	53	0
Package	Installed optional peer edges	47	47	0
Runtime	Unique function payloads	2	2	0
Runtime	Total function bytes	20.52 MB	20.52 MB	+2.4 kB ⚠️
Runtime	Public routes	18	18	0

Changed function payloads vs main (abc130e) (2)

Function	Status	Baseline	Current	Delta	Route changes
`functions/__server.func`	changed	10.26 MB	10.26 MB	+1.2 kB ⚠️	none
`functions/.well-known/workflow/v1/flow.func`	changed	10.26 MB	10.26 MB	+1.2 kB ⚠️	none

`eve init` install

Metric	Baseline	Current	Delta
Installed footprint	116.13 MB	116.14 MB	+4.0 kB ⚠️
Installed packages	115	115	0
dependencies	4	4	0
devDependencies	2	2	0
Dependency package bytes	48.62 MB	48.63 MB	+4.0 kB ⚠️
devDependency package bytes	5.04 MB	5.04 MB	0 B ➖

Build Metadata

Preset: vercel
Nitro: nitro@3.0.260610-beta
Output directory: apps/fixtures/weather-agent/.vercel/output
Build metadata timestamp: 2026-09-04T14:18:12.831Z
Route aliases: 18 public, 1 internal (19 total aliases)
Vercel routes in config: 21
Severity legend: 🔴 dominant/large, 🟠 notable, 🟡 watch, ⚪ small

Package Drill-Down

Package Details

Package: eve@0.51.1
Package directory: packages/eve
Tarball: 8.64 MB (eve-0.51.1.tgz)
Unpacked payload: 32.53 MB across 3823 published files
Installed footprint: 77.70 MB across 7669 installed files
Installed root package: 31.10 MB
Installed dependencies: 46.60 MB
Installed package instances: 35
Distinct installed package names: 34
Installed dependency edges: 53
Installed optional peer edges: 47
Runtime dependencies: 2
Peer dependencies: 5 (4 optional)

Installed footprint is measured from an isolated temporary npm install of the packed tarball.
Graph metrics read only package.json files in package directories directly beneath a node_modules boundary, including nested boundaries. Each directory is one package instance; distinct names come from those manifests. Dependency edges count each unique name in dependencies or optionalDependencies per instance; optional peer edges count peerDependencies marked optional.

Heavy installed dependencies

eve: 31.10 MB (40.0%)
@rolldown/binding-linux-x64-gnu: 19.31 MB (24.9%)
ai: 6.99 MB (9.0%)
zod: 6.41 MB (8.3%)
undici: 3.50 MB (4.5%)

Publish payload breakdown

Published file size
🔴 dist/src/compiled/shadcn-registry/index.js       [#############...........] 9.76 MB 30.0%
🟠 dist/src/compiled/@photon-ai/chat-adapter-ime... [###.....................] 2.27 MB 7.0%
🟠 dist/src/compiled/@ai-sdk/code-mode/index.js     [#.......................] 1.03 MB 3.2%
🟡 dist/src/compiled/@vercel/blob/index.js          [#.......................] 901.8 kB 2.8%
🟡 dist/src/compiled/_chunks/workflow/undici-Dfx... [#.......................] 512.5 kB 1.6%
🔴 Other published files                            [########################] 18.06 MB 55.5%

Installed footprint breakdown

Installed package size
🔴 eve                             [########################] 31.10 MB 40.0%
🔴 @rolldown/binding-linux-x64-gnu [###############.........] 19.31 MB 24.9%
🔴 ai                              [#####...................] 6.99 MB 9.0%
🔴 zod                             [#####...................] 6.41 MB 8.3%
🟠 undici                          [###.....................] 3.50 MB 4.5%
🟠 nitro                           [##......................] 2.41 MB 3.1%
🔴 Other installed packages        [######..................] 7.97 MB 10.3%

Runtime dependencies (2)

Package	Range	Notes
`nitro`	`3.0.260610-beta`
`undici`	`8.9.0`

Peer dependencies (5)

Package	Range	Notes
`@opentelemetry/api`	`^1.0.0`	optional peer
`ai`	`catalog:`
`braintrust`	`^3.0.0`	optional peer
`just-bash`	`^3.1.0`	optional peer
`microsandbox`	`^0.5.0`	optional peer

eve init install drill-down

`eve init` install details

Command: eve init my-agent
Package manager: npm
Installed footprint: 116.14 MB across 9565 installed files
Installed packages: 115 total (109 transitive-only)
dependencies: 4 direct packages totaling 48.63 MB
devDependencies: 2 direct packages totaling 5.04 MB
Other transitive package files: 62.47 MB

Installed footprint is measured from an isolated temporary eve init my-agent using the current packed eve tarball.

Heavy installed dependencies

eve: 31.10 MB (26.8%)
@typescript/typescript-linux-x64: 27.95 MB (24.1%)
@rolldown/binding-linux-x64-gnu: 19.31 MB (16.6%)
zod: 10.37 MB (8.9%)
ai: 6.99 MB (6.0%)

Installed footprint breakdown

Installed package size
🔴 eve                              [########################] 31.10 MB 26.8%
🔴 @typescript/typescript-linux-x64 [######################..] 27.95 MB 24.1%
🔴 @rolldown/binding-linux-x64-gnu  [###############.........] 19.31 MB 16.6%
🔴 zod                              [########................] 10.37 MB 8.9%
🔴 ai                               [#####...................] 6.99 MB 6.0%
🟠 undici                           [###.....................] 3.50 MB 3.0%
🔴 Other installed packages         [#############...........] 16.91 MB 14.6%

dependencies (4)

Package	Range	Installed size	Share
`@vercel/connect`	`1.0.0`	167.9 kB	0.1%
`ai`	`^7.0.82`	6.99 MB	6.0%
`eve`	`file:eve-0.51.1.tgz`	31.10 MB	26.8%
`zod`	`4.5.4`	10.37 MB	8.9%

devDependencies (2)

Package	Range	Installed size	Share
`@types/node`	`24.x`	2.54 MB	2.2%
`typescript`	`7.0.2`	2.50 MB	2.2%

Function Drill-Down

Payload Size Graph

Unique function payload size and share of total
🔴 functions/.well-known/workflow/v1/flow.func     [########################] 10.26 MB 50.0%
🔴 functions/__server.func                         [########################] 10.26 MB 50.0%

Top Function Payloads

🟠 functions/.well-known/workflow/v1/flow.func • 1 public route • 10.26 MB

Metric	Value
Public routes	`/.well-known/workflow/v1/flow`
Runtime	`nodejs24.x`
Handler	`index.mjs`
Payload	10.26 MB
Function files	10.26 MB across 112 files
Traced dependencies	0 B
Signal	🟠 Bundled file `index.mjs` is 2.22 MB (21.7%)

🟠 🔎 Dependency Analysis

📦 Bundled files:

Bundled file size
🟠 index.mjs                   [###########.............] 2.22 MB 21.7%
🟡 _libs/undici.mjs            [#####...................] 980.5 kB 9.6%
🟡 _chunks/esm-CE0tAvRh.mjs    [####....................] 723.5 kB 7.0%
🟡 _chunks/chatgpt-model.mjs   [###.....................] 696.6 kB 6.8%
🟡 _chunks/frames-Boesh7kU.mjs [###.....................] 680.2 kB 6.6%
🔴 Other bundled files         [########################] 4.96 MB 48.3%

🧾 Vercel Config

{
  "handler": "index.mjs",
  "launcherType": "Nodejs",
  "shouldAddHelpers": false,
  "supportsResponseStreaming": true,
  "runtime": "nodejs24.x",
  "maxDuration": "max",
  "experimentalTriggers": [
    {
      "type": "queue/v2beta",
      "topic": "__eve776561746865722d6167656e74_wkf_workflow_*",
      "consumer": "default",
      "retryAfterSeconds": 5,
      "initialDelaySeconds": 0
    }
  ],
  "environment": {
    "WORKFLOW_PRECONDITION_GUARD": "1"
  }
}

🟠 functions/__server.func • 17 public routes, 1 internal alias • 10.26 MB

Metric	Value
Public routes	`/` `/.well-known/workflow/v1/webhook/[token]` `/eve/v1/activity/[token]` `/eve/v1/callback/[token]` `/eve/v1/connections/[name]/callback/[attemptId]/[token]` `/eve/v1/connections/[name]/callback/[token]` `/eve/v1/health` `/eve/v1/info` `/eve/v1/session` `/eve/v1/session/[parentSessionId]/subagents/[callId]/[childSessionId]/stream` `/eve/v1/session/[sessionId]` `/eve/v1/session/[sessionId]/cancel` `/eve/v1/session/[sessionId]/clear` `/eve/v1/session/[sessionId]/compact` `/eve/v1/session/[sessionId]/reset` `/eve/v1/session/[sessionId]/stream` `/eve/v1/task-input/[token]`
Internal aliases	`/__server`
Runtime	`nodejs24.x`
Handler	`index.mjs`
Payload	10.26 MB
Function files	10.26 MB across 112 files
Traced dependencies	0 B
Signal	🟠 Bundled file `index.mjs` is 2.22 MB (21.7%)

🟠 🔎 Dependency Analysis

📦 Bundled files:

Bundled file size
🟠 index.mjs                   [###########.............] 2.22 MB 21.7%
🟡 _libs/undici.mjs            [#####...................] 980.5 kB 9.6%
🟡 _chunks/esm-CE0tAvRh.mjs    [####....................] 723.5 kB 7.1%
🟡 _chunks/chatgpt-model.mjs   [###.....................] 696.6 kB 6.8%
🟡 _chunks/frames-Boesh7kU.mjs [###.....................] 680.2 kB 6.6%
🔴 Other bundled files         [########################] 4.96 MB 48.3%

🧾 Vercel Config

{
  "handler": "index.mjs",
  "launcherType": "Nodejs",
  "shouldAddHelpers": false,
  "supportsResponseStreaming": true,
  "runtime": "nodejs24.x"
}

Build Timing: `e2e/fixtures/agent-tools-sandbox`

This is an informational timing measurement inside eve build, from preflight through publication. Output-size measurement and profile writing are excluded.

Build mode: deployable Vercel build with sandbox template prewarm included.

Build pipeline: 2.96 s -> 2.86 s (-101.8 ms) vs main (abc130e).
Timing is informational: shared GitHub runners are too variable for a hard timing budget.

Detailed phase timings vs `main (abc130e)`

Phase	Baseline	Current	Delta
`extension.check`	14.9 ms	15.0 ms	+0.1 ms
`project.resolve`	0.4 ms	0.4 ms	0.0 ms
`workspace.create`	10.4 ms	15.3 ms	+4.9 ms
`host.prepare`	472.0 ms	461.6 ms	-10.4 ms
`vercel.service-prefix.resolve`	1.6 ms	1.9 ms	+0.3 ms
`nitro.create`	550.3 ms	549.4 ms	-0.9 ms
`sandbox.prewarm`	407.9 ms	278.1 ms	-129.8 ms
`nitro.cache.prepare`	0.2 ms	0.3 ms	+0.1 ms
`nitro.prepare`	0.8 ms	0.8 ms	0.0 ms
`nitro.public-assets`	0.7 ms	0.8 ms	+0.1 ms
`nitro.prerender`	0.4 ms	0.4 ms	0.0 ms
`nitro.bundle`	1.45 s	1.48 s	+34.7 ms
`nitro.cache.write`	0.3 ms	0.3 ms	0.0 ms
`vercel.workflow-function.materialize`	44.2 ms	43.3 ms	-0.9 ms
`agent-summary.emit`	0.7 ms	0.8 ms	+0.1 ms
`nitro.close`	0.1 ms	0.1 ms	0.0 ms
`output.publish`	3.2 ms	3.3 ms	+0.1 ms
`workspace.remove`	2.0 ms	1.9 ms	-0.1 ms

feat(eve): batch model calls within workflow steps

9f0b88f

Signed-off-by: Andrew Barba <barba@hey.com>

vercel Bot deployed to Preview – eve-pkg September 4, 2026 14:15 View deployment

vercel Bot deployed to Preview – eve-docs-4759 September 4, 2026 14:16 View deployment

vercel Bot deployed to Preview – eve-docs September 4, 2026 14:17 View deployment

Navigation Menu

Uh oh!

feat(eve): batch model calls within workflow steps - #3034

feat(eve): batch model calls within workflow steps#3034
AndrewBarba wants to merge 1 commit into
mainfrom
barba/experimental-multi-call-workflow-steps

AndrewBarba commented Sep 4, 2026

Uh oh!

vercel Bot commented Sep 4, 2026 •

edited

Loading

Uh oh!

github-actions Bot commented Sep 4, 2026

Package Details

`eve init` install details

Payload Size Graph

Top Function Payloads

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

1 participant

Uh oh!

Conversation

AndrewBarba commented Sep 4, 2026

Summary

Validation

Checklist

Uh oh!

vercel Bot commented Sep 4, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

github-actions Bot commented Sep 4, 2026

Bundle + Package Summary: apps/fixtures/weather-agent

Delta vs main (abc130e)

eve init install

Package Details

eve init install details

Payload Size Graph

Top Function Payloads

Build Timing: e2e/fixtures/agent-tools-sandbox

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

1 participant

vercel Bot commented Sep 4, 2026 •

edited

Loading

Bundle + Package Summary: `apps/fixtures/weather-agent`

Delta vs `main (abc130e)`

`eve init` install

`eve init` install details

Build Timing: `e2e/fixtures/agent-tools-sandbox`