fix(eve): yield long-running bash commands

[cmpadden]

Summary

Closes #440. A built-in bash call could wait indefinitely when a command ran for a long time or its output stream stalled.

This change makes long-running commands manageable without terminating them:

• New commands wait for up to yieldTimeMs (default: 5 minutes).
• If a command is still running, bash returns a processId and leaves it running.
• Follow-up calls use the same tool with poll, wait, or kill.
• Cancellation terminates the process group and removes its tracked state.
• Results include wallTimeSeconds.
• Each sandbox tracks at most 64 background commands.

Scope and limitations:

• Process ids work only while the underlying sandbox process remains live.
• just-bash supports yielding, polling, and waiting, but not killing because it has no OS process.
• This does not replay commands or recover interrupted command streams.

Validation

Focused coverage confirms the completed, yielded, polled, waited, killed, cancelled, missing-process, and process-cap paths, plus provider-compatible schemas. The command wrapper also recorded the expected exit codes for explicit exit, set -e failure, and exec; the full unit tier and hosted-runtime scenario passed.

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)

Diff size

Docs — 2 files · +7 / -1

Documents yielding, process actions, lifecycle limits, and the release note.

Implementation — 3 files · +448 / -99

Adds bounded foreground waits, process lifecycle management, lightweight status polling, and development progress reporting.

Tests — 6 files · +391 / -43

Covers the process lifecycle, limits, cancellation, public schemas, and prompt-cache fixture isolation.

[vercel]

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

Project	Deployment	Actions	Updated (UTC)
eve-docs	Ready	Preview, v0	Aug 26, 2026 3:10pm
eve-docs-4759	Ready	Preview, v0	Aug 26, 2026 3:10pm
eve-pkg	Ready	Preview, v0	Aug 26, 2026 3:10pm

[github-actions]

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

Key takeaways

• No notable deltas vs main (d79de0b).

Delta vs main (d79de0b)

Area	Metric	Baseline	Current	Delta
Package	Packed tarball	8.22 MB	8.24 MB	+24.1 kB ⚠️
Package	Unpacked publish size	31.00 MB	31.10 MB	+101.6 kB ⚠️
Package	Installed footprint	74.63 MB	74.73 MB	+101.6 kB ⚠️
Package	Published files	3501	3534	+33
Package	Installed files	7216	7249	+33
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	18.37 MB	18.46 MB	+91.8 kB ⚠️
Runtime	Public routes	16	16	0

Changed function payloads vs main (d79de0b) (2)

Function	Status	Baseline	Current	Delta	Route changes
functions/__server.func	changed	9.19 MB	9.23 MB	+45.9 kB ⚠️	none
functions/.well-known/workflow/v1/flow.func	changed	9.19 MB	9.23 MB	+45.9 kB ⚠️	none

eve init install

Metric	Baseline	Current	Delta
Installed footprint	113.07 MB	113.17 MB	+101.6 kB ⚠️
Installed packages	120	120	0
dependencies	4	4	0
devDependencies	2	2	0
Dependency package bytes	45.60 MB	45.70 MB	+101.6 kB ⚠️
devDependency package bytes	5.04 MB	5.04 MB	0 B ➖

eve init dependency changes vs main (d79de0b)

dependencies

• Changed: eve@file:eve-0.44.4.tgz -> eve@file:eve-0.45.0.tgz

Build Metadata

• Preset: vercel
• Nitro: nitro@3.0.260610-beta
• Output directory: apps/fixtures/weather-agent/.vercel/output
• Build metadata timestamp: 2026-08-26T15:05:15.705Z
• Route aliases: 16 public, 1 internal (17 total aliases)
• Vercel routes in config: 19
• Severity legend: 🔴 dominant/large, 🟠 notable, 🟡 watch, ⚪ small

Package Drill-Down

Package Details

• Package: eve@0.45.0
• Package directory: packages/eve
• Tarball: 8.24 MB (eve-0.45.0.tgz)
• Unpacked payload: 31.10 MB across 3534 published files
• Installed footprint: 74.73 MB across 7249 installed files
• Installed root package: 29.74 MB
• Installed dependencies: 44.99 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: 29.74 MB (39.8%)
• @rolldown/binding-linux-x64-gnu: 19.33 MB (25.9%)
• ai: 6.77 MB (9.1%)
• zod: 5.07 MB (6.8%)
• undici: 3.50 MB (4.7%)

Publish payload breakdown

Published file size
🔴 dist/src/compiled/shadcn-registry/index.js       [##############..........] 9.76 MB 31.4%
🟠 dist/src/compiled/@photon-ai/chat-adapter-ime... [####....................] 2.44 MB 7.9%
🟠 dist/src/compiled/experimental-ai-sdk-code-mo... [##......................] 1.51 MB 4.8%
🟡 dist/src/compiled/_chunks/workflow/undici-Dzn... [#.......................] 512.7 kB 1.6%
🟡 dist/src/compiled/_chunks/node/undici-CUIybhQ... [#.......................] 508.8 kB 1.6%
🔴 Other published files                            [########################] 16.37 MB 52.6%

Installed footprint breakdown

Installed package size
🔴 eve                             [########################] 29.74 MB 39.8%
🔴 @rolldown/binding-linux-x64-gnu [################........] 19.33 MB 25.9%
🔴 ai                              [#####...................] 6.77 MB 9.1%
🔴 zod                             [####....................] 5.07 MB 6.8%
🟠 undici                          [###.....................] 3.50 MB 4.7%
🟠 nitro                           [##......................] 2.41 MB 3.2%
🔴 Other installed packages        [######..................] 7.92 MB 10.6%

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: 113.17 MB across 9145 installed files
• Installed packages: 120 total (114 transitive-only)
• dependencies: 4 direct packages totaling 45.70 MB
• devDependencies: 2 direct packages totaling 5.04 MB
• Other transitive package files: 62.43 MB

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

Heavy installed dependencies

• eve: 29.74 MB (26.3%)
• @typescript/typescript-linux-x64: 27.95 MB (24.7%)
• @rolldown/binding-linux-x64-gnu: 19.33 MB (17.1%)
• zod: 9.02 MB (8.0%)
• ai: 6.77 MB (6.0%)

Installed footprint breakdown

Installed package size
🔴 eve                              [########################] 29.74 MB 26.3%
🔴 @typescript/typescript-linux-x64 [#######################.] 27.95 MB 24.7%
🔴 @rolldown/binding-linux-x64-gnu  [################........] 19.33 MB 17.1%
🔴 zod                              [#######.................] 9.02 MB 8.0%
🔴 ai                               [#####...................] 6.77 MB 6.0%
🟠 undici                           [###.....................] 3.50 MB 3.1%
🔴 Other installed packages         [##############..........] 16.86 MB 14.9%

dependencies (4)

Package	Range	Installed size	Share
@vercel/connect	1.0.0	167.9 kB	0.1%
ai	^7.0.58	6.77 MB	6.0%
eve	file:eve-0.45.0.tgz	29.74 MB	26.3%
zod	4.4.3	9.02 MB	8.0%

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     [########################] 9.23 MB 50.0%
🔴 functions/__server.func                         [########################] 9.23 MB 50.0%

Top Function Payloads

🟠 functions/.well-known/workflow/v1/flow.func • 1 public route • 9.23 MB

Metric	Value
Public routes	/.well-known/workflow/v1/flow
Runtime	nodejs24.x
Handler	index.mjs
Payload	9.23 MB
Function files	9.23 MB across 105 files
Traced dependencies	0 B
Signal	🟠 Bundled file index.mjs is 1.82 MB (19.7%)

🟠 🔎 Dependency Analysis

📦 Bundled files:

Bundled file size
🟠 index.mjs                   [##########..............] 1.82 MB 19.7%
🟡 _libs/undici.mjs            [#####...................] 980.5 kB 10.6%
🟡 _chunks/sandbox.mjs         [####....................] 781.9 kB 8.5%
🟡 _chunks/frames-Dl2Hcma4.mjs [####....................] 678.7 kB 7.4%
🟡 _chunks/chatgpt-model.mjs   [####....................] 665.1 kB 7.2%
🔴 Other bundled files         [########################] 4.31 MB 46.7%

🧾 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 • 15 public routes, 1 internal alias • 9.23 MB

Metric	Value
Public routes	/ /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	9.23 MB
Function files	9.23 MB across 105 files
Traced dependencies	0 B
Signal	🟠 Bundled file index.mjs is 1.82 MB (19.7%)

🟠 🔎 Dependency Analysis

📦 Bundled files:

Bundled file size
🟠 index.mjs                   [##########..............] 1.82 MB 19.7%
🟡 _libs/undici.mjs            [#####...................] 980.5 kB 10.6%
🟡 _chunks/sandbox.mjs         [####....................] 781.9 kB 8.5%
🟡 _chunks/frames-Dl2Hcma4.mjs [####....................] 678.7 kB 7.4%
🟡 _chunks/chatgpt-model.mjs   [####....................] 665.1 kB 7.2%
🔴 Other bundled files         [########################] 4.31 MB 46.7%

🧾 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: 2.40 s -> 2.38 s (-19.2 ms) vs main (d79de0b).
• Timing is informational: shared GitHub runners are too variable for a hard timing budget.

Detailed phase timings vs `main (d79de0b)`

Phase	Baseline	Current	Delta
extension.check	1.1 ms	1.1 ms	0.0 ms
project.resolve	0.3 ms	0.3 ms	0.0 ms
workspace.create	0.7 ms	0.7 ms	0.0 ms
host.prepare	343.2 ms	327.4 ms	-15.8 ms
vercel.service-prefix.resolve	2.4 ms	2.4 ms	0.0 ms
nitro.create	259.7 ms	263.7 ms	+4.0 ms
sandbox.prewarm	249.2 ms	220.7 ms	-28.5 ms
nitro.cache.prepare	0.2 ms	0.3 ms	+0.1 ms
nitro.prepare	0.8 ms	0.9 ms	+0.1 ms
nitro.public-assets	0.8 ms	0.8 ms	0.0 ms
nitro.prerender	0.4 ms	0.4 ms	0.0 ms
nitro.bundle	1.49 s	1.51 s	+18.9 ms
nitro.cache.write	0.3 ms	0.4 ms	+0.1 ms
vercel.workflow-function.materialize	43.7 ms	45.9 ms	+2.2 ms
agent-summary.emit	0.7 ms	0.7 ms	0.0 ms
nitro.close	0.1 ms	0.1 ms	0.0 ms
output.publish	3.5 ms	3.5 ms	0.0 ms
workspace.remove	2.1 ms	2.2 ms	+0.1 ms

[vercel]

When sandbox.run for the background launch throws (rather than returning a non-zero exit code), the reserved process directory is never removed and permanently consumes a slot against MAX_BACKGROUND_BASH_PROCESSES.

[cmpadden]

Closing in favor of a clean replacement built around sandbox-managed command handles. The current branch proved the behavior but relies on shell and filesystem process management that does not align with eve's durable step lifecycle.