Head to head · Agent harnesses · October 2026 research run

Agent Zero vs Pi

Pi scores 68.4 (B) on agent readiness against Agent Zero's 54.2 (C), and leads in 6 of 7 scored categories. Both do agent harnesses.

Best agent harnesses and coding agents · All 205 harnesses comparisons

Which one, for what

Agent Zero C

Best for A technical owner who wants an agent with its own Linux machine, reachable from Telegram, WhatsApp or email, with scheduled tasks and editable memory.

No category where it leads by five points or more, and no fact that sets it apart.

Watch for

No approval step before shell commands, file changes or outgoing messages. Tool Access defaults to allow

Pi B

Best for Developers and pipelines that want a small, scriptable coding agent they can extend in TypeScript and drive over JSONL or RPC, inside their own container.

Ahead on

  • Reliability, 75 against 57
  • Schema & documentation, 84 against 64
  • Agent ergonomics, 76 against 62
  • Security & auth, 61 against 54
  • Maintenance & community, 87 against 75
  • Transparency & trust, 64 against 55

Also in its favour

  • Free to start without a card

Watch for

No permission system or sandbox. Tool calls run with the user's rights and without an approval prompt

Score by category

CategoryWeight this runAgent ZeroPiEdge
Reliability16%205775Pi +18
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.26484Pi +20
Agent ergonomics13%16.26276Pi +14
Security & auth14%17.55461Pi +7
Payments & pricing10%12.56060even
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.87587Pi +12
Transparency & trust7%8.85564Pi +9
Negative events≤15-6-4
TotalC 54.2/100B 68.4/100

Facts side by side

FactAgent ZeroPi
KindAgent harnessAgent harness
VendorAgent Zero, s.r.o.Earendil
Hosted endpointno (local only)no (local only)
Transports
AuthNoneNone
PricingFreeFree
x402nono
LicenceMITMIT
Read-only variant documentednono
llms.txtyesno
Last release2026-09-232026-10-07
Terms last updatedno document linkedno document linked
Privacy policy last updatedno document linkedno document linked
Customer content may train models
Terms restrict automated access
Terms restrict benchmarking
Terms or service can change without notice
Arbitration or class-action waiver
Popularity19k stars113k stars, 5.2M npm/wk

Verdicts

Agent Zero

Self-hosted under the MIT licence, with nine releases in the 90 days to 12 October 2026 and breaking changes listed in the release notes. The agent runs shell commands in its container with no approval step, the web interface has no login by default, and five CVEs from the past year have no published GitHub advisory.

Pi

Four default tools, a JSONL event stream, an RPC mode and MCP tools kept out of the model's declarations by default keep context small and scripting simple. Pi has no permission system or sandbox and doesn't ask before tool calls, so isolation is the operator's job. Version 1.0.0 is dated 1 October 2026.

Before you call either

Agent Zero

  1. Set a UI login and password in Settings before publishing the port or opening a tunnel. The default has none
  2. Fill allowed_users, allowed_numbers or sender_whitelist before enabling a channel. An empty list accepts every sender
  3. Enable the Infection Check plugin when the agent reads mail, web pages or MCP results. It ships disabled
  4. Run v2.12 or later. It fixes a Telegram webhook authentication bypass and a WhatsApp media path traversal
  5. Call POST /api_message with the X-API-KEY header. The token changes when the UI login or password changes

Pi

  1. Run Pi inside a container or VM for unattended work. It has no sandbox and doesn't ask before running shell commands
  2. Use pi --mode json and wait for agent_settled. A failed response doesn't set a nonzero exit code in JSON mode
  3. Split the JSONL stream on LF only. Node's readline also splits on U+2028 and U+2029, which are valid inside JSON strings
  4. Pass --no-approve or --approve in scripts to make the project trust decision explicit
  5. Set PI_TELEMETRY=0 and PI_SKIP_VERSION_CHECK=1, or PI_OFFLINE=1, to stop the default requests to pi.dev

Questions

Which is better for AI agents, Agent Zero or Pi?

Pi scores 68.4 (B) on agent readiness against Agent Zero's 54.2 (C), and leads in 6 of 7 scored categories.

Are Agent Zero and Pi open source?

Yes. Agent Zero is open source (MIT). Pi is open source (MIT).

Other comparisons with Agent Zero or Pi

Machine-readable

For companies

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