AI tool comparison
Goose vs Pretty Fish
Which one should you ship with? Here is the side-by-side panel verdict, pricing read, reviewer split, and community vote comparison.
Developer Tools
Goose
The open-source AI agent that actually runs your code
25%
Panel ship
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Community
Paid
Entry
Goose is an open-source, locally-running AI agent built by Block (the company behind Square and Cash App) that goes far beyond code autocomplete. It autonomously installs dependencies, writes and executes code, edits files, runs tests, and manages workflows—all from your machine. Unlike cloud-hosted coding agents, Goose runs entirely local and works with any LLM: OpenAI, Anthropic, Gemini, or your own self-hosted model. The v1.29.0 release (March 31, 2026) adds orchestration support, Gemini-ACP provider integration, tool filtering by MCP metadata visibility, and desktop UI management for sub-agent recipes. It also includes Sigstore/SLSA provenance verification for self-updates and CVE patch for a tar vulnerability—rare signals of production-grade security hygiene in an open-source agent. With 37,000+ GitHub stars and 126 releases, Goose is among the most starred agent projects on GitHub. Its MCP server integration means it plugs into the same ecosystem as Claude, Cursor, and Windsurf—making it a credible self-hosted alternative to Codex or Claude Code for teams that want to own their stack.
Developer Tools
Pretty Fish
Free, beautiful Mermaid diagram editor that works offline
75%
Panel ship
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Community
Free
Entry
Pretty Fish is a free, open-source Mermaid diagram editor with live preview, 5 built-in themes, multi-page workspaces, and one-click SVG/PNG export. It works offline as a Progressive Web App (PWA) and requires no account, no login, and no installation. It supports all 14+ Mermaid diagram types including flowcharts, sequence diagrams, Gantt charts, entity-relationship diagrams, and Git graphs. The editor includes syntax highlighting, auto-completion, instant error feedback, and a clean split-pane layout. The multi-page workspace lets you manage entire diagram projects in a single session. Export quality is excellent — SVG output is clean and scaling-ready for use in presentations, docs, or design systems. Pretty Fish hit Hacker News front page today with 128 points and has the makings of the go-to Mermaid editor for developers who generate diagrams from AI-assisted documentation workflows. With LLMs increasingly generating Mermaid syntax in their outputs, having a polished renderer and editor matters more than ever.
Reviewer scorecard
“Block's engineering pedigree shows here. This isn't a weekend side project—126 releases in, with SLSA provenance, MCP integration, and multi-LLM support baked in. The local execution model is genuinely compelling for anyone worried about sending proprietary code to Anthropic or OpenAI.”
“The official Mermaid live editor is clunky and slow. Pretty Fish loads instantly, works offline, and the multi-page workspace means I can manage all my architecture diagrams in one place. Bookmarking this immediately as my default Mermaid editor.”
“Every agentic coding tool claims to 'run your code autonomously'—the failure modes are where they differ. Without sandboxing, an agent that executes arbitrary shell commands on your machine is a footgun waiting to go off. The CVE patch in the latest release suggests they're still catching basic security issues at 37k stars.”
“It's a genuinely nice editor but it's solving a niche problem — most devs who need Mermaid diagrams already use VS Code extensions or embed them in Notion. And with no backend, there's no collaboration or sharing story, which limits its use in team workflows.”
“The MCP integration is the sleeper feature. Once there are 500 well-maintained MCP servers covering every dev tool, database, and API—Goose becomes the OS-level agent runtime that replaces your entire toolchain. Block's financial infrastructure background also hints at where this goes: autonomous agents managing money flows.”
“As AI tools increasingly output Mermaid syntax to explain architectures and flows, the need for a great rendering environment grows. Pretty Fish positions itself at the intersection of AI-generated diagrams and human editing — that's a well-timed niche.”
“If you're not comfortable reading Rust error logs and configuring LLM API keys, Goose will frustrate you. The dual desktop/CLI interface helps, but the onboarding still assumes you know what MCP is. Not a 'just works' tool for non-engineers—yet.”
“Five beautiful themes and clean SVG exports mean I can finally use Mermaid diagrams in client-facing presentations without them looking like developer scratch notes. This is the Mermaid editor I've always wanted and the zero-friction setup seals it.”
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