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AI agents

Silmaril

Silmaril is the first runtime security for AI that self-improves. It understands application context to block 2x as many threats as current SOTA defenses with 10x lower latency. Customers plug us into agentic frameworks like LangGraph with 5 lines of code. Silmaril has stopped $28M of damages for customers.

sources
1
Evidence entries preserved.
affiliations
1
Y Combinator
competitors
6
Mapped from High Signal graph features.
status
generated
D1 lookup
last updated
2026-07-15
16:41 UTC
source evidence
Why this company exists here

Y Combinator

yc-company-directory #453

Silmaril is the first runtime security for AI that self-improves. It understands application context to block 2x as many threats as current SOTA defenses with 10x lower latency. Customers plug us into agentic frameworks like LangGraph with 5 lines of code. Silmaril has stopped $28M of damages for customers.

source
generated read
High Signal interpretation

Silmaril is classified as AI agents from source descriptions and fund-directory context. Similar companies below are ranked from offline product facets and meaningful description overlap; category and source affiliation can only strengthen an existing product match. For lookup-created rows, the profile starts as pending enrichment until deeper source collection runs.

offline extraction
Product facets
customersSilmarilLangGraphSOTA defensesagentic frameworksruntime security
mapping method
Similarity graph

Local clusters rerank extracted product concepts and description terms. The generated graph remains the fallback for sparse descriptions: offline reciprocal product-similarity graph: extracted concepts + description terms + bounded category/affiliation boosts. Minimum fallback score: 0; max competitors: 6.

discovery cluster

Companies similar to Silmaril

AI agents · 6 peers

A deterministic local cluster built from offline product facets and meaningful description terms. Category and selected-institution affiliation provide bounded tie-breaks. Open any peer to continue exploring its cluster.

RASPIRE

match 93

RASPIRE is the first line of defense for applications against AI-powered fraud attacks, API abuse, and runtime threats. Unlike code scanners and pentesting tools that identify vulnerabilities before release, RASPIRE operates like a security expert running inside applications, monitoring, detecting, and blocking attacks 24/7 in real time. All without writing a single line of code.

shared extracted concept terms: runtime; shared product terms: line, defense, application, runtime; shared product theme: developer infrastructure, security and compliance; shared affiliation: Y Combinator

Cotool

match 61

Cotool is an agentic security platform that eliminates manual and repetitive work for security teams. Today’s cybersecurity teams remain bogged down by alert fatigue, context switching, and documentation overhead. Security teams don't need more dashboards with "AI-powered insights" — they need their time back. Cotool empowers teams to build security their way. Our platform provides an AI co-pilot that automatically assembles context across tools, a no-code agent builder that transforms successfu

shared extracted concept terms: security; shared product terms: agentic, security, context, code; shared product theme: context and memory, developer infrastructure, security and compliance; same category: AI agents; shared affiliation: Y Combinator

Reworkd

match 58

At Reworkd, we're working on multimodal LLM agents that serve as the simplest way to extract web data at scale. Customers come to us with lists of 100s to 1000s of websites along with a data schema. Our agents traverse these websites, understand their structure, and generate code to extract data from them. We've been working on LLM agents since their inception and have received over 30k stars on GitHub and 1M+ users across previous agent products. If you're interested in our pilot program, shoot

shared extracted concepts: customers; shared product terms: customer, us, understand, code; shared product theme: developer infrastructure, sales and marketing; same category: AI agents; shared affiliation: Y Combinator

Fixture

match 55

Fixture is an AI-native CRM built for startups. It integrates with all the tools you use to communicate with customers, tracks marketing channels (e.g. website traffic), and pulls everything into a single go-to-market context store. Our AI agents proactively help you move your deals forward, and you can use Fixture from our web UI or any of your favorite AI tools (e.g. Claude Code).

shared extracted concepts: customers; shared product terms: customer, context, code; shared product theme: context and memory, developer infrastructure, sales and marketing; same category: AI agents; shared affiliation: Y Combinator

transload

match 54

transload helps logistics companies measure shipments using the security cameras they already have. A pallet, a couch, a tire – we capture its true size as it moves through the warehouse. For our customers, 15% of shipments turn out to be bigger than what the sender claimed. Catching those differences is worth ~$50k per site per month in rebillings and improved trailer utilization.

shared extracted concepts: customers; shared product terms: security, customer; shared product theme: context and memory, sales and marketing, security and compliance; shared affiliation: Y Combinator

Supabase

match 54

Supabase is the easiest way to get started with Postgres. Each project within Supabase is an isolated Postgres cluster, allowing customers to scale independently, while still providing the features that you need to build: instant database setup, auth, row level security, realtime data streams, auto-generating APIs, and a simple to use web interface. We are 100% remote.

shared extracted concepts: customers; shared product terms: customer, security; shared product theme: developer infrastructure, sales and marketing, security and compliance; shared affiliation: Y Combinator