feat(eve): stream local tool generator results

[ctgowrie]

Summary

Tools may now use async generators to stream local preliminary output snapshots. Each snapshot is normalized at the execute boundary and emitted as action.partial (stream version 21); the last yield remains the terminal action.result and the only value exposed to the model.

The durable emitter coalesces adjacent same-call snapshots while busy. The default client reducer projects those snapshots as output-available dynamic tool parts with partial: true, clears the flag on the terminal result, and ignores replayed partials after settlement. Hook, channel, and extension contracts include the new event. Provider preliminary results and MCP progress notifications remain unchanged.

Validation

• pnpm test:unit
• pnpm typecheck
• pnpm lint
• pnpm docs:check
• pnpm guard:invariants
• pnpm update:extension-contracts
• Added a CI-only agent-tools eval for preliminary generator output; e2e execution is CI-only by repository policy.

Checklist

• I linked an issue with prior discussion confirming this change is wanted
• 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)

[vercel]

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

Project	Deployment	Actions	Updated (UTC)
eve-docs	Ready	Preview	Aug 5, 2026 5:29pm
eve-docs-4759	Ready	Preview, v0	Aug 5, 2026 5:29pm

[github-actions]

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

Key takeaways

• No notable deltas vs main (56de47b).

Delta vs main (56de47b)

Area	Metric	Baseline	Current	Delta
Package	Packed tarball	7.65 MB	7.65 MB	+5.3 kB ⚠️
Package	Unpacked publish size	28.68 MB	28.69 MB	+8.2 kB ⚠️
Package	Installed footprint	72.01 MB	72.02 MB	+8.2 kB ⚠️
Package	Published files	3026	3030	+4
Package	Installed files	6725	6729	+4
Runtime	Unique function payloads	2	2	0
Runtime	Total function bytes	16.98 MB	16.98 MB	+3.4 kB ⚠️
Runtime	Public routes	13	13	0

Changed function payloads vs main (56de47b) (2)

Function	Status	Baseline	Current	Delta	Route changes
functions/__server.func	changed	8.49 MB	8.49 MB	+1.7 kB ⚠️	none
functions/.well-known/workflow/v1/flow.func	changed	8.49 MB	8.49 MB	+1.7 kB ⚠️	none

eve init install

Metric	Baseline	Current	Delta
Installed footprint	110.42 MB	110.43 MB	+8.2 kB ⚠️
Installed packages	121	121	0
dependencies	4	4	0
devDependencies	2	2	0
Dependency package bytes	43.09 MB	43.10 MB	+8.2 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: 2026-08-05T17:29:34.177Z
• Route aliases: 13 public, 1 internal (14 total aliases)
• Vercel routes in config: 16
• Severity legend: 🔴 dominant/large, 🟠 notable, 🟡 watch, ⚪ small

Package Drill-Down

Package Details

• Package: eve@0.30.6
• Package directory: packages/eve
• Tarball: 7.65 MB (eve-0.30.6.tgz)
• Unpacked payload: 28.69 MB across 3030 published files
• Installed footprint: 72.02 MB across 6729 installed files
• Installed root package: 27.33 MB
• Installed dependencies: 44.68 MB
• Runtime dependencies: 2
• Peer dependencies: 5 (4 optional)

Installed footprint is measured from an isolated temporary npm install of the packed tarball.

Heavy installed dependencies

• eve: 27.33 MB (38.0%)
• @rolldown/binding-linux-x64-gnu: 19.35 MB (26.9%)
• ai: 6.60 MB (9.2%)
• zod: 5.07 MB (7.0%)
• undici: 3.50 MB (4.9%)

Publish payload breakdown

Published file size
🔴 dist/src/compiled/shadcn-registry/index.js       [#################.......] 9.68 MB 33.8%
🟠 dist/src/compiled/@photon-ai/chat-adapter-ime... [####....................] 2.42 MB 8.4%
🟠 dist/src/compiled/experimental-ai-sdk-code-mo... [###.....................] 1.51 MB 5.2%
🟡 dist/src/compiled/_chunks/node/undici-DWL_MYm... [#.......................] 502.4 kB 1.8%
🟡 dist/src/compiled/_chunks/workflow/undici-DWL... [#.......................] 502.4 kB 1.8%
🔴 Other published files                            [########################] 14.07 MB 49.1%

Installed footprint breakdown

Installed package size
🔴 eve                             [########################] 27.33 MB 38.0%
🔴 @rolldown/binding-linux-x64-gnu [#################.......] 19.35 MB 26.9%
🔴 ai                              [######..................] 6.60 MB 9.2%
🔴 zod                             [####....................] 5.07 MB 7.0%
🟠 undici                          [###.....................] 3.50 MB 4.9%
🟠 nitro                           [##......................] 2.41 MB 3.3%
🔴 Other installed packages        [#######.................] 7.76 MB 10.8%

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	^3.0.0	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: 110.43 MB across 8605 installed files
• Installed packages: 121 total (115 transitive-only)
• dependencies: 4 direct packages totaling 43.10 MB
• devDependencies: 2 direct packages totaling 5.04 MB
• Other transitive package files: 62.29 MB

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

Heavy installed dependencies

• @typescript/typescript-linux-x64: 27.95 MB (25.3%)
• eve: 27.33 MB (24.8%)
• @rolldown/binding-linux-x64-gnu: 19.35 MB (17.5%)
• zod: 9.02 MB (8.2%)
• ai: 6.60 MB (6.0%)

Installed footprint breakdown

Installed package size
🔴 @typescript/typescript-linux-x64 [########################] 27.95 MB 25.3%
🔴 eve                              [#######################.] 27.33 MB 24.8%
🔴 @rolldown/binding-linux-x64-gnu  [#################.......] 19.35 MB 17.5%
🔴 zod                              [########................] 9.02 MB 8.2%
🔴 ai                               [######..................] 6.60 MB 6.0%
🟠 undici                           [###.....................] 3.50 MB 3.2%
🔴 Other installed packages         [##############..........] 16.67 MB 15.1%

dependencies (4)

Package	Range	Installed size	Share
@vercel/connect	0.4.3	141.0 kB	0.1%
ai	^7.0.38	6.60 MB	6.0%
eve	file:eve-0.30.6.tgz	27.33 MB	24.8%
zod	4.4.3	9.02 MB	8.2%

devDependencies (2)

Package	Range	Installed size	Share
@types/node	24.x	2.54 MB	2.3%
typescript	7.0.2	2.50 MB	2.3%

Function Drill-Down

Payload Size Graph

Unique function payload size and share of total
🔴 functions/.well-known/workflow/v1/flow.func     [########################] 8.49 MB 50.0%
🔴 functions/__server.func                         [########################] 8.49 MB 50.0%

Top Function Payloads

🟠 functions/.well-known/workflow/v1/flow.func • 1 public route • 8.49 MB

Metric	Value
Public routes	/.well-known/workflow/v1/flow
Runtime	nodejs24.x
Handler	index.mjs
Payload	8.49 MB
Function files	8.49 MB across 43 files
Traced dependencies	0 B
Signal	🟠 Bundled file index.mjs is 2.31 MB (27.2%)

🟠 🔎 Dependency Analysis

📦 Bundled files:

Bundled file size
🟠 index.mjs                       [#######################.] 2.31 MB 27.2%
🟠 _chunks/runtime-artifacts.mjs   [################........] 1.62 MB 19.1%
🟡 _libs/undici.mjs                [##########..............] 980.5 kB 11.5%
🟡 _chunks/sandbox.mjs             [########................] 769.0 kB 9.1%
🟡 _libs/@ai-sdk/gateway+[...].mjs [####....................] 432.8 kB 5.1%
🟠 Other bundled files             [########################] 2.38 MB 28.0%

🧾 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 • 12 public routes, 1 internal alias • 8.49 MB

Metric	Value
Public routes	/ /eve/v1/callback/[token] /eve/v1/connections/[name]/callback/[token] /eve/v1/health /eve/v1/info /eve/v1/session /eve/v1/session/[sessionId] /eve/v1/session/[sessionId]/cancel /eve/v1/session/[sessionId]/stream /eve/v1/session/clear /eve/v1/session/compact /eve/v1/session/reset
Internal aliases	/__server
Runtime	nodejs24.x
Handler	index.mjs
Payload	8.49 MB
Function files	8.49 MB across 43 files
Traced dependencies	0 B
Signal	🟠 Bundled file index.mjs is 2.31 MB (27.2%)

🟠 🔎 Dependency Analysis

📦 Bundled files:

Bundled file size
🟠 index.mjs                       [#######################.] 2.31 MB 27.2%
🟠 _chunks/runtime-artifacts.mjs   [################........] 1.62 MB 19.1%
🟡 _libs/undici.mjs                [##########..............] 980.5 kB 11.5%
🟡 _chunks/sandbox.mjs             [########................] 769.0 kB 9.1%
🟡 _libs/@ai-sdk/gateway+[...].mjs [####....................] 432.8 kB 5.1%
🟠 Other bundled files             [########################] 2.38 MB 28.0%

🧾 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: 1.94 s -> 2.05 s (+107.0 ms) vs main (56de47b).
• Timing is informational: shared GitHub runners are too variable for a hard timing budget.

Detailed phase timings vs `main (56de47b)`

Phase	Baseline	Current	Delta
extension.check	9.3 ms	1.0 ms	-8.3 ms
project.resolve	2.6 ms	0.6 ms	-2.0 ms
workspace.create	1.3 ms	0.6 ms	-0.7 ms
host.prepare	276.0 ms	147.3 ms	-128.7 ms
vercel.service-prefix.resolve	1.6 ms	2.1 ms	+0.5 ms
nitro.create	193.4 ms	224.4 ms	+31.0 ms
sandbox.prewarm	170.3 ms	382.6 ms	+212.3 ms
nitro.cache.prepare	0.3 ms	0.2 ms	-0.1 ms
nitro.prepare	0.8 ms	0.8 ms	0.0 ms
nitro.public-assets	0.7 ms	0.7 ms	0.0 ms
nitro.prerender	0.5 ms	0.4 ms	-0.1 ms
nitro.bundle	1.26 s	1.26 s	+1.6 ms
nitro.cache.write	0.3 ms	0.3 ms	0.0 ms
vercel.workflow-function.materialize	18.5 ms	20.1 ms	+1.6 ms
agent-summary.emit	0.4 ms	0.5 ms	+0.1 ms
nitro.close	0.2 ms	0.2 ms	0.0 ms
output.publish	3.2 ms	3.2 ms	0.0 ms
workspace.remove	1.7 ms	1.7 ms	0.0 ms