Skip to content
effecthub

CoreStory vs Swimm

Two fact sheets from our own research, side by side — pricing, platforms, API access and status re-checked by us rather than quoted from the vendors. Only CoreStory ships a public API.

CoreStoryBuilds a persistent map of what a codebase does and exposes it to engineers and AI coding agents.SwimmStatic analysis plus AI that reads legacy code and writes the documentation and diagrams a migration team needs.

Side by side

FactCoreStorySwimm
CategoryDocumentation GeneratorsDocumentation Generators
Pricing modelContactContact
Public APIYesNo
PlatformsWeb, APIWeb, Vscode Ext
CompanyCoreStorySwimm
Launched—2019
Last verifiedSep 1, 2026Sep 6, 2026

What our research says

CoreStory

CoreStory is aimed at the specific pain of large, old codebases that no single engineer fully understands anymore, and its MCP/API hook into coding agents is a genuinely useful idea — giving an AI agent real architectural context instead of just the files it can see. It's an enterprise sale with no public pricing, so it isn't something a solo developer or small team can just sign up for and try today.

Pros

  • MCP and API integration lets coding agents query real system context during planning
  • Targets the specific, underserved problem of legacy-codebase understanding
  • Well-funded ($32M Series A) with enterprise customers already in production

Cons

  • No public pricing — every plan requires talking to sales
  • No self-serve trial details visible without providing contact information
  • Broad positioning (architects, PMs, new hires, AI agents all at once) makes it hard to tell who it's built for first

Swimm

Swimm is the rare documentation tool that treats old code as the source of truth instead of asking humans to describe it. If you are staring at a COBOL or .NET estate nobody understands, the flow maps and extracted business rules are the useful part. The catch is that it is no longer a tool you can simply buy: it is a staged engagement with engineers attached, and the self-serve documentation product it was known for is not what the site sells today.

Pros

  • Deterministic static analysis backs the AI output, so traces come from the code rather than a guess
  • Produces diagrams and flow maps, not only prose
  • Covers mainframe and COBOL alongside .NET and Java
  • Work is broken into fixed-price stages you can stop after

Cons

  • No pricing published anywhere on the site
  • Repositioned away from the continuous-documentation product it was known for
  • Aimed at large estates, which makes it overkill for a normal repository

Which one fits

Choose CoreStory if you need

  • Enterprises modernizing large legacy codebases
  • Teams that want AI coding agents to have real architectural context, not just file contents

Choose Swimm if you need

  • Teams documenting a mainframe or legacy .NET/Java estate before a migration
  • Architects who need job-flow and variable traces out of unfamiliar code
  • Enterprises that want non-engineers to read what the code actually does

More comparisons

Browse all Documentation Generators →