Brad Menezes, CEO of enterprise vibe coding startup Superblocks, believes the following crop of billion-dollar startup concepts are hiding in nearly plain sight: the system prompts utilized by present unicorn AI startups.
System prompts are the prolonged prompts — over 5,000-6,000 phrases — that AI startups use to instruct the foundational fashions from corporations like OpenAI or Anthropic on generate their application-level AI merchandise. They’re, in Menezes view, like a grasp class in immediate engineering.
“Each single firm has a very totally different system immediate for a similar [foundational] mannequin,” he instructed TechCrunch. “They’re attempting to get the mannequin to do precisely what’s required for a particular area, particular duties.”
System prompts aren’t precisely hidden. Prospects can ask many AI instruments to share theirs. However they aren’t at all times publicly obtainable.
In order a part of his personal startup’s new product announcement of an enterprise coding AI agent named Clark, Superblocks provided to share a file of 19 system prompts from a few of the hottest AI coding merchandise like Windsurf, Manus, Cursor, Lovable and Bolt.
Menezes’s tweet went viral, seen by nearly 2 million together with massive names within the Valley like Sam Blond, previously of Founders Fund and Brex, and Aaron Levie, a Superblocks investor. Superblocks introduced final week that it raised a $23 million Collection A extension spherical, bringing its complete Collection A to $60 million for its vibe coding instruments geared to non-developers at enterprises.
So we requested Menezes to stroll us by means of examine different’s system prompts to glean insights.
“I’d say the most important studying for us constructing Clark and studying by means of the system prompts is that the system immediate itself is perhaps 20% of the key sauce,” Menezes defined. This immediate offers the LLM the baseline of what to do.
The opposite 80% is “immediate enrichment” he mentioned, which is the infrastructure a startup builds across the calls to the LLM. That half consists of directions it attaches to a person’s immediate, and actions taken when returning the response, reminiscent of checking for accuracy.
Roles, context and instruments
He mentioned there are three components of system prompts to check: function prompting, contextual prompting, and gear use.
The very first thing to note is that, whereas system prompts are written in pure language, they’re exceptionally particular. “You mainly have to talk as if you happen to would to a human co-worker,” Menezes mentioned. “And the directions need to be excellent.”
Position prompting helps the LLMs be constant, giving each goal and persona. For example, Devin’s begins with, “You might be Devin, a software program engineer utilizing an actual laptop working system. You’re a actual code-wiz: few programmers are as gifted as you at understanding codebases, writing practical and clear code, and iterating in your adjustments till they’re appropriate.”
Contextual prompting offers the fashions the context to think about earlier than appearing. It ought to present guardrails that may, as an illustration, scale back prices and guarantee readability on duties.
Cursor’s instructs, “Solely name instruments when wanted, and by no means point out instrument names to the person — simply describe what you’re doing. … don’t present code except requested. … Learn related file content material earlier than modifying and repair clear errors, however don’t guess or loop fixes greater than thrice.”
Instrument use allows agentic duties as a result of it instructs the fashions transcend simply producing textual content. Replit’s, as an illustration, is lengthy and describes modifying and looking code, putting in languages, organising and querying PostgreSQL databases, executing shell instructions and extra.
Learning others’ system prompts helped Menezes see what different vibe coders emphasised. Instruments like Loveable, V0, and Bolt “deal with quick iteration,” he mentioned, whereas “Manus, Devin, OpenAI Codex, and Replit” assist customers create full-stack functions however “the output remains to be uncooked code.”
Menezes noticed a chance to let non-programmers write apps, if his startup might deal with extra, reminiscent of safety and entry to enterprise knowledge sources like Salesforce.
Whereas he’s not but working the multi-billion startup of his goals, Superblocks has landed some notable corporations as prospects, it mentioned, together with Instacart and Paypaya World.
Menezes can also be dogfooding the product internally. His software program engineers aren’t allowed to put in writing inside instruments; they’ll solely construct the product. So his enterprise people have constructed brokers for all their wants, like one which makes use of CRM knowledge to determine leads, one which tracks help metrics, one other that stability the assignments of the human gross sales engineers.
“That is mainly a manner for us to construct the instruments and never purchase the instruments,” he says.
Correction: This story was up to date to make clear that the majority not too long ago introduced spherical was an extension spherical and to replace the Collection A complete quantity raised.
