PromptShark vs Skillier.ai

PromptShark and Skillier.ai are both inference engines & infra tracked by AIDiveForge. Below is a side-by-side comparison of pricing, capabilities, platforms, and ownership — sourced from each tool's live website and verified before publishing.

PromptShark

PromptShark is a local MITM proxy written in Go and C++ that sits between your agent and any OpenAI-compatible API endpoint. Every request and response pair is captured, logged, and surfaced in a real-time dashboard — no changes to your agent code, just a single base_url swap. The loop detector flags infinite tool-calling cycles automatically. The time-travel replay feature lets you re-run or edit any historical API step without firing a live request, which means no extra token spend during debugging. The self-hosted, MIT-licensed architecture means your prompts and API keys never leave your own infrastructure.

Skillier.ai

Skillier sits between you and your AI client, detecting what domain you're working in and loading the relevant skill — finance modeling, legal reasoning, DevOps runbooks — into the context without you leaving the interface. The Lite version is MIT-licensed and runs offline, which matters for air-gapped environments where cloud-dependent tooling is a non-starter. The routing model hands control back through an AskUserQuestion prompt, so you confirm the skill selection rather than having it decided for you. That model works cleanly for single-domain sessions. Blended workflows — writing copy while checking financial assumptions, for instance — require you to manually re-route between skills, and the seams show.

Attribute	PromptShark	Skillier.ai
Pricing	Free	Paid
Free trial	No	No
Open source	Yes	No
Has API	Yes	No
Self-hosted option	Yes	Yes
Platforms	Cross-platform (Go binary + Docker)	Claude Desktop, Claude Web, Claude Code CLI, OpenClaw
Pros	Zero-instrumentation integration via a single base_url swap, so you get full request visibility without touching your agent's codebase or adding an SDK dependency. Automatic infinite tool-calling loop detection, which means runaway agent cycles are flagged before they drain your token budget rather than after you read the invoice. Per-step token usage and USD cost tracking surfaced in real time, so you can attribute spend to specific agent decisions rather than receiving an opaque monthly total. Time-travel replay lets you re-run and edit any past API step without issuing a live request, so iterating on a prompt variant costs nothing in tokens during a debugging session. MIT-licensed and fully self-hostable via Docker, which means your prompts, responses, and API keys remain on your own infrastructure with no third-party data handling.	Offline skill access via the self-hostable Lite version, so air-gapped teams and low-connectivity environments can load domain expertise without a live API call — something cloud-only tools in this category cannot offer. Skill routing that triggers without leaving the chat interface, which means the context window you've built up in a session doesn't get abandoned every time you need to shift to a different domain. MIT-licensed Lite version with no paid tier required, so teams that need to audit, fork, or self-host the code have a legal path to do that without a procurement conversation. Explicit AskUserQuestion confirmation before a skill loads, so you stay in control of what gets injected into context — preventing the silent prompt stuffing that degrades output quality when auto-routing guesses wrong.
Cons	The proxy is scoped to OpenAI-compatible API calls; agents using Anthropic, Google, or other non-OpenAI-format endpoints get no coverage, and teams with a mixed provider setup gain only partial visibility. The docs describe no multi-user access controls or role separation, so the tool cannot be safely exposed across a development team without additional network-layer restrictions — teams beyond a single developer typically add a separate access layer or switch to a purpose-built observability platform. There is no alerting or notification system described in the repository; when a loop fires at 2 AM, the dashboard captures it, but nobody is paged — teams with production monitoring requirements move to a dedicated tracing platform such as LangSmith or Langfuse that integrates with existing alerting pipelines. With only 3 commits and 1 star at the time of curation, the project is early-stage; the community reports no track record of sustained maintenance, which is a real risk if you build a debugging workflow around it and a breaking API change in the upstream OpenAI spec goes unpatched.	Multi-domain sessions hit the routing model's friction ceiling fast: each skill switch requires a confirmation prompt, so a workflow that blends financial modeling with technical writing generates repeated interruptions — teams doing this regularly report falling back to manual context pasting because it's faster. No API surface is described, which means teams who want to embed skill routing inside a pipeline, a CI step, or any system outside Claude Desktop and Claude Web have no integration path — at that point they are looking at building their own context-injection layer or switching to a tool that exposes programmatic control. Scoped exclusively to Claude Desktop and Claude Web at time of review, so organizations standardized on other AI clients — GPT-4 via ChatGPT, Gemini, or internal models — get no benefit and need a different solution entirely.

Bottom line

PromptShark is free while Skillier.ai is paid; PromptShark is open source; only PromptShark exposes a public API. Choose based on which difference matters most for your workflow.

Frequently asked questions

What is the difference between PromptShark and Skillier.ai?

PromptShark is Free and open source, while Skillier.ai is Paid. Compare pricing, free trial, API, platforms, and pros/cons in the table above on AIDiveForge.

Is PromptShark better than Skillier.ai?

It depends on your workflow. Use the side-by-side attributes (pricing, open source, API, self-hosted, platforms) to decide. AIDiveForge does not rank a universal winner — we publish verified facts so you can choose.