Borrowing it
Nothing to install: this file belongs to yaalalabs/agent-kernel. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/yaalalabs/agent-kernel/develop/.agents/skills/ak-dev-new-sandbox-provider/SKILL.mdgit clone --depth 1 https://github.com/yaalalabs/agent-kernelWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/yaalalabs/agent-kernel/ak-dev-new-sandbox-provider)<a href="https://agentmods.dev/skills/yaalalabs/agent-kernel/ak-dev-new-sandbox-provider"><img src="https://agentmods.dev/badge/skills/yaalalabs/agent-kernel/ak-dev-new-sandbox-provider/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/yaalalabs/agent-kernel/ak-dev-new-sandbox-provider"><img src="https://agentmods.dev/badge/skills/yaalalabs/agent-kernel/ak-dev-new-sandbox-provider.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00092 | $0.04783 |
| Opus 5.5 | $0.00037 | $0.01913 |
| Sonnet 5.5 | $0.00018 | $0.00957 |
| Haiku 4.5 | $0.00009 | $0.00478 |
Grade A, and why
ak-dev-new-sandbox-provider scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured today.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 339 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Adding a New Sandbox Provider
This guide walks through adding a new sandbox provider to Agent Kernel. Use the shipped
local_subprocess (ak-py/src/agentkernel/sandbox/providers/local_subprocess.py) and
docker (ak-py/src/agentkernel/sandbox/providers/docker.py) implementations as reference.
Existing Providers
| Provider | type value |
Isolation | Extra |
|---|---|---|---|
| Local subprocess | local_subprocess |
none (no isolation; dev/test) |
— (stdlib) |
| Docker | docker |
container |
agentkernel[sandbox-docker] |
| E2B | e2b |
micro_vm |
agentkernel[e2b] |
| Daytona | daytona |
container |
agentkernel[daytona] |
| EC2 via SSM | ec2_ssm |
none (attach-only to an existing instance) |
agentkernel[aws] |
| Kubernetes | kubernetes |
container |
agentkernel[kubernetes] |
Planned in later iterations: bedrock_agentcore.
Reference implementations by pattern: docker.py (sync SDK via to_thread), e2b.py
(native async SDK + native idle timeout passthrough), daytona.py (sync SDK + native
auto-stop + configurable base image/snapshot/env_vars + resource mapping), ec2_ssm.py
(attach-only provider with user-identity
mapping: sts:AssumeRole + run_as), kubernetes.py (sync SDK via to_thread with plain
dict manifests, exec over the WebSocket stream API (the caller's RBAC needs BOTH create
and get on pods/exec), user identity via cached per-subject RBAC-impersonation clients,
and the instance-level capability override, below). Providers with a native auto-stop take
the profile's idle_timeout as a second constructor argument, passed by their factory
branch; kubernetes takes it too, sizing the pod's activeDeadlineSeconds orphan ceiling.
Attach-only backends (environments the framework connects to but never owns) subclass
AttachedEnvironmentProvider instead of SandboxProvider: it fixes create (binds to the
config's attach_to, never provisions) and destroy (no-op) once, so only attach is
implemented. The handle subclasses AttachedEnvironment (not Sandbox directly), which fixes
close() as a no-op and keeps the class name honest (e.g. EC2SSMEnvironment). Declare
provisions=False, attaches_external=True — the factory validates the profile's
environment: managed | attached mode against these flags at startup (attach-only providers
are rejected under managed, and attached requires attaches_external plus an attach_to
target), and the worker never self-heal-provisions or disposes an attached environment.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- today Changed 9ac2f9b0cab4
- yesterday Changed · +62 lines b7604da7bd2f
- 1mo ago Changed · +5 lines 8bb0de14fdf6
- 1mo ago Changed · +7 lines b4c4ce8208c5
- 2mo ago Changed · +13 lines · +4 tokens per session 92c43acfa85a
- 2mo ago First seen · 252 lines · 88 tokens per session scan A 09b08ff314a4
ak-dev-new-sandbox-provider is a skill published in the GitHub repository yaalalabs/agent-kernel (192 stars, last pushed yesterday), licensed Apache-2.0. It adds 92 tokens to every session and 4,783 once invoked, about $0.0004 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
ak-dev-new-sandbox-provider compared with skills from other repositories
| Mod | Type | Stars | Last push | Licence | Scan | Tokens | Works with |
|---|---|---|---|---|---|---|---|
| ak-dev-new-sandbox-provideryaalalabs/agent-kernel | Skill | 192 | yesterday | Apache-2.0 | A | 92 | Claude Code, Codex |
| cloud-native-security-defensivej4flmao/agent-skills | Skill | 38 | 3d ago | MIT | A | 127 | Claude Code, Codex |
| notionArvo-AI/aurora | Skill | 454 | yesterday | Apache-2.0 | A | 23 | Claude Code |
| datadogArvo-AI/aurora | Skill | 454 | yesterday | Apache-2.0 | A | 28 | Claude Code |
| scalewayArvo-AI/aurora | Skill | 454 | yesterday | Apache-2.0 | A | 29 | Claude Code |
| terrasharkLukasNiessen/terrashark | Skill | 710 | 4d ago | MIT | A | 56 | Claude Code, Codex |
| isaac-automatorisaac-sim/IsaacAutomator | Skill | 270 | 11d ago | Apache-2.0 | A | 123 | Claude Code, Codex |