AI tool comparison
AgentAuth by Composio 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
AgentAuth by Composio
OAuth and credential management for AI agents acting on user behalf
75%
Panel ship
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Community
Free
Entry
AgentAuth is a dedicated OAuth management service from Composio that handles authentication flows and credential storage so AI agents can securely act on behalf of users across third-party services. It ships as both a standalone SDK and an MCP server, letting developers drop credential orchestration into existing agent architectures without building it themselves. The core problem it solves is the gnarly plumbing of multi-tenant token storage, refresh cycles, and scoped permissions inside agentic workflows.
Developer Tools
Pretty Fish
Free, beautiful Mermaid diagram editor that works offline
75%
Panel ship
—
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
“The primitive here is multi-tenant OAuth token lifecycle management with a surface designed for agent runtimes — that's a real problem that every team building agents hits at hour four and ignores until it bites them in production. The DX bet is 'give us the plumbing, keep your agent logic clean,' and the SDK-plus-MCP-server dual-deployment story is the right call — it meets you where your stack already is. My hesitation is that the pricing isn't public and the docs I can get to don't show what the token storage model looks like under the hood; I want to know if this is a Postgres-backed credential store I can inspect or a black box I'm trusting with user tokens before I commit.”
“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.”
“The category is agent authentication infrastructure, and the direct competitors are rolling your own with Auth0 plus a secrets manager, or using Nango, which has been solving this problem longer and has public pricing. AgentAuth's specific bet is that MCP-native delivery is a wedge — if MCP becomes the dominant agent protocol, being the OAuth layer for it is a real position; if MCP stalls, this is a niche SDK competing on convenience alone. What kills this in 12 months: the major agent platforms — LangChain, CrewAI, the cloud providers — ship a first-party auth primitive and AgentAuth becomes an integration tax instead of a solution. To stay relevant, Composio needs to become the credential network effect, not just the pipe.”
“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 buyer here is the engineering team at a company building production AI agents, and the budget is infrastructure or platform tooling — that's a real budget line. The problem: pricing is not public, which in a category where Nango ships transparent tiers and Auth0 has a calculator means you're asking buyers to enter a sales conversation before they've validated the integration works for them, and that kills self-serve adoption in developer tools. The moat claim is the Composio ecosystem and the MCP server distribution, but if the underlying value is 'we store and refresh your OAuth tokens,' that's a feature not a company — the moment a hyperscaler or an agent framework ships a first-party credential vault, the standalone business case collapses unless there's a network effect in the token graph I'm not seeing yet.”
“The thesis AgentAuth bets on: within two years, AI agents will be the primary initiators of third-party API calls on behalf of human users, and the OAuth 2.0 consent model was not designed for non-human principals acting at scale — creating a structural gap that a purpose-built layer can own. That's a falsifiable and plausible claim, and the dependency is that agents become genuinely multi-step and multi-service, not just single-tool wrappers, which the current trajectory supports. The second-order effect nobody is talking about: if AgentAuth becomes the credential broker for a significant slice of agent traffic, they accumulate a dataset of which services agents actually use and how — that's a positioning and intelligence asset that compounds in ways pure OAuth plumbing doesn't. They're early to this specific framing, which is the right time to be here, but early also means they have to educate the market on why this isn't just 'use a secrets manager.'”
“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.”
“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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