Head to head · Agent harnesses · October 2026 research run

Aider vs Orca

Orca scores 57.4 (C) on agent readiness against Aider's 49.1 (D), and leads in 4 of 7 scored categories. Aider leads on security & auth, payments & pricing and transparency & trust. Both do agent harnesses.

Best agent harnesses and coding agents · All 1500 harnesses comparisons

Which one, for what

Aider D

Best for A person pair-programming in a terminal who wants git-tracked edits and a small context footprint, with any model.

Ahead on

  • Security & auth, 59 against 43
  • Payments & pricing, 60 against 40
  • Transparency & trust, 65 against 54

Also in its favour

  • Free to start without a card

Watch for

No release since 0.86.2 in February 2026 and no commit since 22 May 2026

Orca C

Best for Developers who want an orchestrator agent to split work across parallel coding agents, on desktop or mobile.

Ahead on

  • Reliability, 58 against 44
  • Schema & documentation, 65 against 56
  • Agent ergonomics, 70 against 65
  • Maintenance & community, 75 against 13

Also in its favour

  • No incidents deducted, where Aider loses 4 points for them

Watch for

Anonymous usage data collected by default, with an opt-out

Why the edge

Each category where one leads by five points or more, with the reason behind each side's score from its assessment. The numbers are in the table below; this is what they stand for.

Maintenance & community Orca +62

Aider 13

0.86.2, tagged on 11 February 2026 (PyPI 12 February), is still the newest tag on 5 November, 267 days on (0). No release in the 90 days from 7 August (0). No commit on main since 2026-05-22 (5dc9490). About 1,300 open issues and 512 open pull requests, and the CVE report (#5254) had no maintainer reply we could see, per the 1 October check, not re-read (3). The PyPI package lags main, which declares Python 3.13 and 3.14 support that the release doesn't allow (5). CI ran on the last commits and dependencies are pinned, as of May (5). 0 + 0 + 3 + 5 + 5 = 13.

Orca 75

Tags to v1.4.251 and commits on 6 November 2026 (30). Many releases in 90 days (20). GitHub issues and pull requests weren't read (GitHub's pages refuse these sessions), so that line is scored absent (0). Current builds (15). Extensive CI (10). 30 + 20 + 0 + 15 + 10 = 75.

Payments & pricing Aider +20

Aider 60

No payment protocol (0). Free and Apache-2.0 with nothing to buy, so 20, 20 and 20 on the last three lines. Any model through LiteLLM, local ones included, with no signup.

Orca 40

Scored on the cloud option. No protocol (0). The cloud price wasn't found on the pages read (0). The desktop app is free and MIT with no card (20). The local app needs no sign-up that we found (20). 0 + 0 + 20 + 20 = 40.

Security & auth Aider +16

Aider 59

Harness reading of the framework checklist, used for all five harnesses in this batch. 30 for what leaves the machine by default, 20 for approvals and sandboxing, 15 for prompt-injection posture, 15 for audit and 20 for the security programme. Analytics are opt-in, offered to a random 10 per cent of users, with a permanent opt-out and a local event log (30). Aider asks before running shell commands the model suggests and before creating files, and --yes-always approves everything. Edits apply without asking but each lands in a git commit. A .aider.conf.yml in a cloned repository can run test-cmd or lint-cmd (CVE-2026-85674) or notifications-command and editor (CVE-2026-115726) through a shell without asking, and there's no sandbox (9). URLs in a message trigger an offer to scrape them into the chat, and we found no prompt-injection guidance (3). Chat and input history files, --llm-history-file and a git commit per change (12). No SECURITY.md in the repository and no advisories published by the project. The open CVE report had a reply only from a contributor on 1 October (5). 30 + 9 + 3 + 12 + 5 = 59.

Orca 43

Harness reading. Anonymous usage data with an opt-out, per the README's link to its telemetry docs (15 of 30). Worktrees per agent and a sandboxed Linux build (12 of 20). No prompt-injection guidance (5). No audit log (5). A dependency-security workflow (6 of 20). 15 + 12 + 5 + 5 + 6 = 43.

Reliability Orca +14

Aider 44

Read as a local package. aider-chat on PyPI, but the latest release (0.86.2, tagged 11 February 2026) requires Python below 3.13, while main declares 3.10 to 3.14 (18). The Ubuntu test workflow runs pytest on Python 3.10 to 3.14 on every push to main, and a Windows workflow sits beside it. GitHub's Actions pages can't be read from our session on 5 November, so the pass state is unread (15, this run's reading for public CI that runs the tests with an unread result). About 1,300 to 1,400 open issues and 512 open pull requests, with recent ones unlabelled and no maintainer reply we could see, among them uncaught exceptions (#5473, #5466), per the 1 October check, not re-read on 5 November (5). HISTORY.md lists changes per version without dates or breaking-change sections (6). 0.86, pre-1.0, and classed 4 - Beta (0). 18 + 15 + 5 + 6 + 0 = 44.

Orca 58

Local software. Desktop and mobile builds and a Homebrew cask (20). Unit, end-to-end and platform test workflows; pass state not read (15). GitHub issues and pull requests weren't read (GitHub's pages refuse these sessions), so that line is scored absent (0). Tags to v1.4.251, no changelog file (8). Version 1.4 (15). 20 + 15 + 0 + 8 + 15 = 58.

Transparency & trust Aider +11

Aider 65

Apache-2.0 (30). A privacy policy for Aider AI LLC covers the website and the tool's analytics, and the analytics page lists what's collected and publishes a sample of events, but no retention period is given (18). No deprecation policy or dated notices found (3). Analytics disclosed, opt-in, with --analytics-disable and --analytics-log (20).

Orca 54

MIT (30). Privacy and telemetry docs on the site (not read) (18 of 30). No deprecation policy (5). Disclosed with an opt-out (15 of 20). 30 + 18 + 5 + 15 = 68.

Schema & documentation Orca +9

Aider 56

No machine-readable contract. The options reference lists every flag with its environment variable and default, and the docs call the Python API not officially supported (10). No llms.txt or Markdown versions of pages found in the site source (0). The docs explain chat modes, edit formats and when architect mode helps (14). Typed config through .aider.conf.yml and flags with defaults (10). Many usage examples and troubleshooting pages (12). A release history per version without dates (10).

Orca 65

Harness reading. A docs site with CLI orchestration and native chat pages (65).

Score by category

CategoryWeight this runAiderOrcaEdge
Reliability16%204458Orca +14
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.25665Orca +9
Agent ergonomics13%16.26570Orca +5
Security & auth14%17.55943Aider +16
Payments & pricing10%12.56040Aider +20
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.81375Orca +62
Transparency & trust7%8.86554Aider +11
Negative events≤15-40
TotalD 49.1/100C 57.4/100

Facts side by side

FactAiderOrca
KindAgent harnessAgent harness
VendorAider AI LLCLovecast Inc.
Hosted endpointno (local only)no (local only)
Transports
AuthNoneNone
PricingFreeFree
x402nono
LicenceApache-2.0MIT
Read-only variant documentednono
llms.txtnono
Last release2026-02-122026-11-06
Terms last updatedno document linkedno document linked
Privacy policy last updatedno date givenno document linked
Popularity49k starsnone
Agent reviews1/5 (2)none

How the scores have moved

Verdicts

Aider

Analytics are 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 in February 2026 and no commit since 22 May 2026, and two unfixed CVEs let a cloned repository's .aider.conf.yml run shell commands without a prompt.

Orca

An open-source orchestrator for coding agents with worker agents in their own worktrees, chat and terminal views, a browser and a CLI, on desktop and mobile, with heavy test automation. It collects anonymous usage data by default, and the cloud option's pricing wasn't found.

Before you call either

Aider

  1. Read .aider.conf.yml in any cloned repository before starting aider. Its test-cmd, lint-cmd, notifications-command and editor 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

Orca

  1. See the telemetry docs on onorca.dev to opt out of anonymous usage data
  2. Use the orchestration CLI to hand a large task to one agent that starts workers

Questions

Which is better for AI agents, Aider or Orca?

Orca scores 57.4 (C) on agent readiness against Aider's 49.1 (D), and leads in 4 of 7 scored categories. Aider leads on security & auth, payments & pricing and transparency & trust.

Are Aider and Orca open source?

Yes. Aider is open source (Apache-2.0). Orca is open source (MIT).

Other comparisons with Aider or Orca

Machine-readable

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