The decision in a minute
The short version
Try ReplyPilot for the recurring comment task; consider HARPA when that reply is one step in a larger browser routine. Compare the effort of producing a usable sentence in your actual setup.
Choose ReplyPilot when
Start at the comment box
Type /rp on a supported desktop LinkedIn post, generate and review. [1]
Choose HARPA AI when
Build around reusable commands
Reply writing plus configurable page-aware commands, AI connections and monitoring. [8][9]
HARPA belongs on this shortlist because it already does reply writing. Its guide covers summaries, responses, tone settings and pasting a draft into a text field, with LinkedIn among the supported websites. [6]
Both products can draft LinkedIn replies; the difference is how you reach the draft and what else you want the extension to do. [1][8]
A practical comparison
Side by side
Compare the documented workflow and the tradeoffs you will feel in daily use.
| What matters | ReplyPilot | HARPA AI |
|---|---|---|
| Reply entry point | /rp in a supported LinkedIn comment field. [1] | Reply Writer, or Finish Writing from your draft. [6][7] |
| Context | The supported post workflow. [1] | Selected text, summaries and page-aware prompts. [8][6] |
| Voice | Tone, style and custom instructions. [2] | Tone, personal facts and chosen or custom response styles. [6] |
| Reusable setup | Saved reply settings. [2] | Custom commands with parameters and multiple steps. [9] |
| AI connection | The documented ReplyPilot generation flow. [1] | CloudGPT, provider web sessions or API keys. [8] |
| Wider work | This comparison covers LinkedIn comments. [1] | Web monitoring and scheduled automation, with plan conditions. [8][11] |
| Draft handoff | Review before posting. [1] | Copy or paste the generated reply into a field. [6] |
HARPA can finish the thought you already have
Its Finish Writing guide describes starting with a brief draft, invoking the command through a quick access bar or //F, and using webpage context to complete it. LinkedIn is explicitly listed. That is a relevant alternative if you tend to write rough notes before asking for help. [7]
Picture a recruiter answering a post about skills assessments. Her note says: “Good for screening, but who checks false negatives?” The assistant should preserve that question. Reject a draft that turns it into blanket agreement or invents a hiring result. The same standard applies to a ReplyPilot draft: the useful input is her concern, not a request to sound impressive.
HARPA rewards a repeatable routine
Custom commands can combine steps and substitute parameters such as page content into a prompt. HARPA also lets you choose among cloud, web-session and API connections. These are concrete reasons to investigate it when you want to reuse the same research or writing process. [9][8]
That flexibility introduces choices worth testing: which connection you will use, which context the command includes, and which instructions remain appropriate across posts. A reusable command can prevent repeated setup, but you still need a specific point to make about each post. Keep the saved rules general and supply the specific observation each time.
Check where your text goes after local processing
HARPA’s policy says page data is processed locally before being sent to the chosen language-model provider. Page Aware mode is off by default; commands, page parameters and explicitly configured monitors can also access content. Scheduled automations or monitors can operate in the background when configured. [10]
Local processing does not mean the text stays on your computer. Check which provider receives it and what the command sends. Compare those terms with ReplyPilot’s privacy policy. [10][3]
Test the reply separately from the automation
A proposed trial: choose three public LinkedIn posts you would answer anyway. Write your intended point in plain language, then use both extensions with equivalent instructions. Count the edits needed to remove vague praise, unnecessary length and unsupported claims. Read each finished comment aloud before deciding whether you would use it.
Next, test a HARPA command you would actually reuse outside commenting. Its extra value may justify the suite even if the reply drafts are similar. Keep that result separate from writing quality. We have not measured generation speed, engagement or editing effort, and a vendor’s automation features do not establish permission under LinkedIn’s rules. [5]
The cost of the workflow
Pricing and value
Compare the connection and allowance, as well as the plan.
HARPA offers limited free/demo access, subscriptions and a one-time option. Cloud tokens, web sessions and your own API keys have different cost and usage implications; scheduled commands also depend on the tier. Check the live plan table and checkout instead of treating “lifetime” as unlimited third-party AI processing. [11]
Compare that complete setup with ReplyPilot’s current plan and generation limits. [4]
Common questions
Can HARPA write a LinkedIn reply?
Yes. Its Reply Writer and Finish Writing documentation explicitly include LinkedIn. We did not test a logged-in account. [6][7]
Does HARPA support personal tone?
Its reply guide describes tone, personal facts and response-style controls. ReplyPilot offers tone, style and custom instructions too. [6][2]
Does local processing mean no external processing?
No. HARPA’s policy describes sending locally processed page data to the chosen language-model provider. Review that connection’s terms. [10]
Which would you try first for comments?
Try your existing HARPA setup first if you already use it. Try ReplyPilot when its supported /rp flow is the recurring job you want to evaluate. [1]
Research notes
Sources and disclosure
We checked these primary sources on . The notes explain what each reference supports. Product descriptions and policies do not replace a test of your own account.
Who wrote this comparison?
Published by ReplyPilot from public first-party documentation checked 4 October 2026. No hands-on benchmark or security audit. Scenarios are illustrative; the trial is a proposed evaluation.
- ReplyPilot: getting started
Desktop Chrome/Chromium workflow: open a supported LinkedIn post comment box, type /rp, generate, and review before posting.
- ReplyPilot: reply panel settings and customization
Tone, style, personalization, and the Custom Instructions field. These describe controls, not a measured guarantee of draft quality.
- ReplyPilot: privacy policy
Published collection, retention, service-provider, and deletion terms; this is a policy reference, not an independent security audit.
- ReplyPilot: current pricing
Check the live checkout for current plans and limits. No fixed ReplyPilot price is asserted in these comparisons.
- LinkedIn: User Agreement
Platform terms govern third-party tools and automation; a vendor description does not establish platform permission.
- HARPA: Reply Writer
Summary-to-reply flow, tone controls, copy/paste handoff and LinkedIn coverage. Vendor documentation checked 4 October 2026.
- HARPA: Finish Writing
Draft completion with webpage context, quick access and //F; includes LinkedIn. No performance claim adopted.
- HARPA: getting started
Page-aware chat, provider connections, commands and monitoring. Current account behavior was not tested.
- HARPA: custom commands
Reusable command steps and prompt parameters; capability does not establish platform permission.
- HARPA: privacy policy
Local page processing, selected-provider transfer, explicit page access and configured background monitoring; policy review only.
- HARPA: plans and billing FAQ
Free/demo restrictions, subscription and one-time options, token and connection terms. Check current checkout; no fixed amount asserted.