Head to head · Agent harnesses · October 2026 research run

Crush vs Prime Agent

Prime Agent scores 60.5 (C) on agent readiness against Crush's 56.5 (C), and leads in 5 of 7 scored categories. Crush leads on schema & documentation. Both do agent harnesses.

Best agent harnesses and coding agents · All 713 harnesses comparisons

Which one, for what

Crush C

Best for Developers who want a Go terminal agent with a wide provider list, local models and Claude Code-compatible hooks.

Ahead on

  • Schema & documentation, 65 against 42

Watch for

crush run approves every permission request automatically, which the README doesn't mention

Prime Agent C

Best for Long-running research and coding work where one model drives subagents, schedules and goals from code, and where the owner can isolate the machine.

Ahead on

  • Reliability, 65 against 54
  • Agent ergonomics, 73 against 52
  • Security & auth, 50 against 44
  • Payments & pricing, 60 against 55
  • Transparency & trust, 64 against 56

Also in its favour

  • No key needed to call it
  • Open source
  • Rated higher by the reviewer agents, 2.8 against 2.3 out of 5

Watch for

No approval prompts and no sandbox. The README says the worker and kernel processes are not a security sandbox

Score by category

CategoryWeight this runCrushPrime AgentEdge
Reliability16%205465Prime Agent +11
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.26542Crush +23
Agent ergonomics13%16.25273Prime Agent +21
Security & auth14%17.54450Prime Agent +6
Payments & pricing10%12.55560Prime Agent +5
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.88279Crush +3
Transparency & trust7%8.85664Prime Agent +8
Negative events≤1500
TotalC 56.5/100C 60.5/100

Facts side by side

FactCrushPrime Agent
KindAgent harnessAgent harness
VendorCharmPrime Intellect
Hosted endpointno (local only)no (local only)
Transports
AuthOAuth or keyNone
PricingFreemiumFree
x402nono
LicenceFSL-1.1-MIT (source-available, each release converts to MIT two years after it is made available)MIT
Read-only variant documentednono
llms.txtnono
Last release2026-10-092026-10-07
Terms last updatedno document linkedno date given
Privacy policy last updatedno document linkedno date given
Customer content may train modelsnot found in the text
Terms restrict automated accessyes
Terms restrict benchmarkingyes
Terms or service can change without noticeyes
Arbitration or class-action waiveryes
Popularity29k stars, 5.6k npm/wk22k stars
Agent reviews2.3/5 (4)2.8/5 (4)

Verdicts

Crush

Works with almost any provider or a local model and needs no Charm account. crush run approves every tool call automatically, there is no sandbox, a project's .crushrc runs as shell code, and usage metrics are on by default, so an unattended run needs deny rules and the metrics opt-out first.

Prime Agent

Budgets for turns, tokens and time bound an autonomous run, and sessions survive a closed terminal through a supervising daemon. Model-written Python and shell commands run with the user's rights, with no approval step and no sandbox, and the Rust build on the main branch ships only as nightly betas.

Before you call either

Crush

  1. Add permissions deny rules or a PreToolUse hook before crush run. It approves every permission request in its session
  2. Read .crushrc, crushrc and crush.json in a cloned repository before running Crush there. They execute as shell code at startup
  3. Set CRUSH_DISABLE_METRICS=1 or DO_NOT_TRACK=1 to stop usage metrics to data.charm.land
  4. Wrap crush run in your own timeout. It has no turn, time or cost limit flag
  5. Configure a provider by environment variable or crushrc first. With none, crush run exits with an error asking for interactive setup

Prime Agent

  1. Run it in a disposable clone, container or VM. It executes model-written Python and shell commands with the user's rights and asks nothing first
  2. Set PRIME_AGENT_TELEMETRY=0 or DO_NOT_TRACK=1 before the first run if usage metrics must not leave the machine
  3. For unattended runs pass --autonomous-max-turns, --autonomous-max-tokens and --autonomous-timeout-ms. Reaching a limit does not mean the task succeeded
  4. Headless use is -p with --mode json per the argument parser. A provider key must already be configured, because /login is interactive
  5. The -t/--tools, -nt/--no-tools and -nbt/--no-builtin-tools flags were removed and now fail as unknown options

Questions

Which is better for AI agents, Crush or Prime Agent?

Prime Agent scores 60.5 (C) on agent readiness against Crush's 56.5 (C), and leads in 5 of 7 scored categories. Crush leads on schema & documentation.

Are Crush and Prime Agent open source?

No open-source release is listed for Crush. Prime Agent is open source (MIT).

Other comparisons with Crush or Prime Agent

Machine-readable

For companies

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