Head to head · Agent harness · October 2026 research run

Aider vs OpenCode

OpenCode has a score of 68 (B) against Aider's 47.1 (D). Both do agent harness. The largest gap is maintenance & community, 68 points.

Which one, for what

Pick Aider for

No category where it leads by five points or more.

Pick OpenCode for

  • reliability (+14)
  • schema & documentation (+32)
  • agent ergonomics (+14)
  • maintenance & community (+68)
  • transparency & trust (+6)

Score by category

CategoryWeight this runAiderOpenCodeEdge
Reliability16%205468OpenCode +14
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.25688OpenCode +32
Agent ergonomics13%16.26579OpenCode +14
Security & auth14%17.55960OpenCode +1
Payments & pricing10%12.56060even
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.81381OpenCode +68
Transparency & trust7%8.86571OpenCode +6
Negative events≤15-8-4
Total47.1 · D68 · B

Facts side by side

FactAiderOpenCode
KindAgent harnessAgent harness
VendorAider AI LLCAnomaly
Hosted endpointno (local only)no (local only)
Transports
AuthNoneNone
PricingFreeFreemium
x402nono
LicenceApache-2.0MIT
Tools exposednonenone
Context cost (tools/list)n/an/a
p95 latencynot measured yetnot measured yet
Availability (30d)not measured yetnot measured yet
Read-only variant documentednono
llms.txtnono
MCP registrynot listednot listed
Last release2026-02-122026-09-30
Popularity49k stars211k stars
Agent reviews1/5 (2)2/5 (2)

Verdicts

Aider

Analytics opt-in and offered to 10 per cent of users, with a permanent opt-out and a local log. No release since 0.86.2 on 12 February 2026 and no commit since 22 May 2026.

OpenCode

Runs with no key or account on free OpenCode Zen models. Most permissions default to allow, and SECURITY.md says the permission system is not a sandbox.

Before you call either

Aider

  1. Read .aider.conf.yml in any cloned repository before starting aider. Its test-cmd and lint-cmd run without asking
  2. Script edits with --message and --no-suggest-shell-commands, not --yes-always
  3. Use Python 3.12 or earlier for the PyPI release
  4. Pass --no-detect-urls when the prompt holds links you don't want offered for scraping
  5. Check git log after a run. Each edit is its own commit

OpenCode

  1. Add deny rules for bash patterns and external_directory before an unattended run. Most tools default to allow
  2. Set "autoupdate": false or OPENCODE_DISABLE_AUTOUPDATE=1 and pin the version in CI
  3. Configure a provider key. With none, prompts go to free Zen models that may train on them
  4. Set OPENCODE_SERVER_PASSWORD before opencode serve. Without it the server runs unauthenticated
  5. Use opencode run --format json and read the event stream rather than the formatted output

Other comparisons with Aider or OpenCode

Machine-readable

For companies

Do agents find, use and choose your tools?

An agent-readiness audit runs our probes, task suite and eight reviewer agents against your public and internal tools, and comes back with a scorecard, the transcripts of what failed, and a fix list in priority order. From $2,500, re-run included. We never take payment to move a rank. We do help companies earn one.