AI tool comparison
Eyeball vs Tendril
Which one should you ship with? Here is the side-by-side panel verdict, pricing read, reviewer split, and community vote comparison.
Developer Tools
Eyeball
Embeds source screenshots in AI analysis to kill hallucinations
75%
Panel ship
—
Community
Free
Entry
Eyeball is a GitHub Copilot CLI plugin with a deceptively simple idea: instead of trusting the AI to accurately summarize documents, it captures screenshots of the actual source material and embeds them alongside the AI's claims in the output report. If the model says "Section 10 requires mutual indemnification," the report shows that exact section highlighted in yellow directly below the claim. The underlying insight is sharp — screenshots cannot be hallucinated. Text can be subtly reworded, paraphrased incorrectly, or synthesized from nowhere. But a screenshot is a literal capture of the source. Built for legal review, compliance analysis, financial due diligence, and any domain where the stakes of an AI error are high. Built by indie developer dvelton, it handles PDFs, Word documents, and web pages. MIT licensed, free to use. Surfaced on Hacker News Show HN today, where it sparked an active discussion about AI verification and the underrated value of visual evidence in AI-assisted analysis workflows.
Developer Tools
Tendril
An agent that writes, registers, and reuses its own tools — forever
50%
Panel ship
—
Community
Free
Entry
Tendril is an open-source desktop agent built on a radically minimal architecture: instead of giving an AI model dozens of pre-built tools, it gives the model exactly three — search capabilities, register capabilities, and execute code. When you ask it to do something it can't yet do, it writes the tool, registers it, and runs it. The next time you ask for something similar, the tool already exists. Built with Tauri, React, and Node.js on the frontend, and AWS Bedrock (Claude) for inference, Tendril runs code in sandboxed Deno environments for safety. The capability registry grows organically across sessions, meaning the agent becomes measurably more capable the longer you use it — without any retraining or fine-tuning. The "too many tools" problem is a real issue in production agents: large tool lists degrade model reasoning and increase hallucination rates. Tendril's inversion of this pattern — grow tools from need, not configuration — is a genuine architectural contribution. It's MIT licensed and free to use, though AWS Bedrock access for Claude adds ongoing inference costs.
Reviewer scorecard
“This is one of those ideas that makes you think 'why isn't every AI analysis tool doing this?' The implementation is simple — capture screenshots of the source during analysis — but the trust it builds in the output is enormous. I'd use this immediately for any contract or regulatory review workflow.”
“The bootstrap-three-tools architecture is elegant and addresses a real failure mode. Watching an agent build its own scraper and then reuse it 20 minutes later without being told to is genuinely impressive. The Deno sandbox makes it safe enough to experiment with seriously.”
“Screenshots prove the source exists but don't verify the AI's interpretation of it is correct. A model can still misread highlighted text or draw wrong conclusions. Also, PDF-to-screenshot pipelines get messy with scanned documents, multi-column layouts, and complex tables — exactly the docs where hallucinations are most likely.”
“Self-written tools accumulate technical debt fast — a poorly written capability that gets reused across sessions can silently spread bad behavior. There's no audit trail or quality gate for registered tools, which is a serious concern in any shared environment.”
“Eyeball points toward a future of verifiable AI outputs — not just 'the model said this' but 'the model said this, here's the evidence, here's the reasoning chain.' Legal AI adoption hinges on explainability, and embedded source screenshots are a practical step toward outputs that hold up under professional scrutiny.”
“This is a prototype of what persistent agent intelligence looks like: not a model that forgets between sessions, but one that accretes capability. The capability registry pattern will likely influence how production agent systems are architected in the next two years.”
“For research, journalism, and content work where you're citing sources, this is a game-changer. The ability to produce a report where every claim is visually anchored to the source makes the output publishable rather than just useful. The design of the output document matters — would love to see more control over the visual layout.”
“Requires AWS Bedrock setup, a Tauri desktop build, and comfort with the idea that your agent is writing its own code. That's three friction points too many for most non-developers. The concept is brilliant; the UX isn't there yet.”
Weekly AI Tool Verdicts
Get the next comparison in your inbox
New AI tools ship daily. We compare them before you waste an afternoon.