Tessl
Tessl helps AI agents stay reliable and aligned by grounding their work in specs. Agents are powerful, but they can drift — misinterpreting requests, hallucinating APIs, or breaking existing features when adding new ones. Tessl integrates with most agents and uses spec-driven development to give agents (and you) a structured way to capture intent, run tests, and evolve codebases with fewer mistakes.
- Location
- London, United Kingdom, United Kingdom
- Founded
- 2020
- Category
- AI
- Funding
- VC-backed
- Team
- 11–50
Frequently asked questions
What does Tessl do?
Tessl helps AI agents stay reliable and aligned by grounding their work in specs. Agents are powerful, but they can drift — misinterpreting requests, hallucinating APIs, or breaking existing features when adding new ones. Tessl integrates with most agents and uses spec-driven development to give agents (and you) a structured way to capture intent, run tests, and evolve codebases with fewer mistakes.
Where is Tessl based?
Tessl is based in London, United Kingdom, United Kingdom.
When was Tessl founded?
Tessl was founded in 2020.
How much has Tessl raised?
Tessl is vc-backed. Funding details have not been disclosed.
How Tessl would pitch themselves
○ Auto-generated01Target customer
Companies + developers adopting AI in their stack — from indie builders to enterprise ML teams working on keep your ai agents on rails.
02Problem they solve
Tessl helps AI agents stay reliable and aligned by grounding their work in specs. Agents are powerful, but they can drift — misinterpreting requests, hallucinating APIs, or breaking existing features when adding new one… The category has historically been served by tools that miss the modern workflow this product is built around.
03Key differentiator
Tessl differentiates on keep your ai agents on rails — focusing on a specific edge in this category vs. broader incumbents.
04Go-to-market strategy
Series-A scaling stage — building outbound sales motion, hiring first AEs, layering on customer success. Mix of PLG (where the product allows) + direct sales for higher-ACV deals.