<?xml version="1.0" encoding="utf-8" standalone="yes"?><rss version="2.0" xmlns:atom="http://www.w3.org/2005/Atom" xmlns:content="http://purl.org/rss/1.0/modules/content/"><channel><title>File Search on RockB</title><link>https://baeseokjae.github.io/tags/file-search/</link><description>Recent content in File Search on RockB</description><image><title>RockB</title><url>https://baeseokjae.github.io/images/og-default.png</url><link>https://baeseokjae.github.io/images/og-default.png</link></image><generator>Hugo</generator><language>en-us</language><lastBuildDate>Wed, 02 Sep 2026 07:01:52 +0000</lastBuildDate><atom:link href="https://baeseokjae.github.io/tags/file-search/index.xml" rel="self" type="application/rss+xml"/><item><title>Captain (YC W26) Review 2026: Automated RAG for Files Explained</title><link>https://baeseokjae.github.io/posts/captain-automated-rag-files-2026/</link><pubDate>Wed, 02 Sep 2026 07:01:52 +0000</pubDate><guid>https://baeseokjae.github.io/posts/captain-automated-rag-files-2026/</guid><description>Captain (YC W26) is an API-first, self-tuning RAG platform that turns cloud storage files into one queryable index for AI agents. Review of pricing, features, and verdict.</description><content:encoded><![CDATA[<p>Captain is an API-first, self-tuning file search and fully-managed RAG retrieval platform from the Y Combinator W26 batch, founded by Lewis Lien Polansky (CEO) and Edgar Babajanyan. It indexes cloud storage (S3, R2, GCS, Supabase, Backblaze) and SaaS sources like Google Drive into one queryable index, exposing a single query API designed for AI agents rather than end-user knowledge apps.</p>
<p>This 2026 review breaks down what Captain actually does, its five-layer architecture, real pricing based on the published rate card, how it compares to DIY RAG and rivals like Vertex File Search and Glean, the Ragie shutdown signal, and whether it is worth adopting for production teams in 2026.</p>
<h2 id="what-is-captain-yc-w26">What Is Captain (YC W26)?</h2>
<p>Captain positions itself as &ldquo;automated RAG for files,&rdquo; but the shorthand undersells the product. Unlike end-user knowledge assistants such as Glean, Onyx, or Sana, which wrap retrieval in a human-facing chat UI, Captain is developer-managed and agent-agnostic. It exists behind one JSON query API that an AI agent can call deterministically, with the retrieval stack — chunking, embedding, re-ranking, permissions, and continuous re-indexing — fully managed by the platform.</p>
<p>The company is a Y Combinator W26 batch company, launched with a Hacker News &ldquo;Launch HN&rdquo; post titled &ldquo;Captain (YC W26) – Automated RAG for Files&rdquo; that reached roughly 57 points at launch. The founding team explicitly frames the alternative they are attacking: &ldquo;the largest alternative is folks trying to build file search themselves — a lot to manage,&rdquo; naming Google Vertex File Search as the closest incumbent product, while distinguishing Captain from OpenSearch (a low-level engine), Glean/Onyx/Sana (end-user assistants), and Kore.ai (agent orchestration).</p>
<h2 id="how-does-captain-automate-rag-for-files">How Does Captain Automate RAG for Files?</h2>
<p>Captain ships five layers as one product rather than forcing teams to assemble them from separate tools. Understanding these five layers explains what &ldquo;automated&rdquo; actually means in practice.</p>
<h3 id="the-five-layers">The Five Layers</h3>
<ol>
<li><strong>Search</strong>: A sub-second, deterministic API with filters and re-ranking. Determinism is the load-bearing claim — a RAG stack that returns different results on every call is unusable for production agents that need to act on retrieved context.</li>
<li><strong>Iterate</strong>: MCP-triggered evaluation loops that self-tune via <code>captain_eval</code>. This is the &ldquo;self-tuning&rdquo; part of the marketing: instead of manually inspecting chunk sizes and retry strategies, teams run evals that nudge the retrieval configuration automatically.</li>
<li><strong>Process</strong>: Multimodal extraction that handles scans, handwriting, tables, screenshots, audio, and video — moving beyond the plain-text-only ceiling of most RAG pipelines.</li>
<li><strong>Engine</strong>: A unified, multi-provider search core that combines vector search with BM25 keyword retrieval.</li>
<li><strong>Sync</strong>: Event-driven synchronization plus a scheduled sweep, so files added or changed in source storage appear in the index without manual re-import scripts.</li>
</ol>
<p>The combination matters because &ldquo;talk to my files with a vector database&rdquo; is table stakes by 2026. What Captain sells is the operational glue — keeping the index fresh, extracting meaning from non-text files, and self-tuning — that teams routinely underestimate when they build in-house.</p>
<h2 id="captain-pricing-and-credits-in-2026">Captain Pricing and Credits in 2026</h2>
<p>Pricing is transparent, credit-based, and published on the runcaptain.com pricing page. The unit of consumption is a &ldquo;credit,&rdquo; with different rates per content type.</p>
<table>
  <thead>
      <tr>
          <th>Plan</th>
          <th>Monthly Cost</th>
          <th>Included Credits</th>
          <th>Queries</th>
          <th>Overage</th>
      </tr>
  </thead>
  <tbody>
      <tr>
          <td>Developer</td>
          <td>$0/mo</td>
          <td>500 credits</td>
          <td>1,000/mo</td>
          <td>$0.005/query</td>
      </tr>
      <tr>
          <td>Startup</td>
          <td>$1,600/mo</td>
          <td>83,000 credits</td>
          <td>Unlimited</td>
          <td>$0.015/credit</td>
      </tr>
      <tr>
          <td>Enterprise</td>
          <td>Custom</td>
          <td>Custom</td>
          <td>Custom</td>
          <td>BYOC/on-prem, AWS PrivateLink, GCP Private Service Connect</td>
      </tr>
  </tbody>
</table>
<p>Credit pricing by content type breaks down as follows: Text processing at $0.02 per page (no OCR), Basic processing at $0.02 per page, Advanced at $0.05 per page (vision/layout for tables, charts, and scans), Image at $0.01, Audio at $0.10 per minute, Video at $0.40 per minute, and Copy Collection at $0.20.</p>
<p>During the launch discussion, founders cited a real-world scenario of roughly 15,000 credits (about 1,000 pages of new content per month) at approximately $295 per month for unlimited queries on a startup-style plan. The Startup plan on the current rate card is $1,600/mo for 83,000 credits, which implies the earlier figure reflected an advanced/basic processing-tier distinction that has since been consolidated.</p>
<h2 id="captain-vs-diy-rag-vs-competitors">Captain vs. DIY RAG vs. Competitors</h2>
<p>The decision for most teams is not &ldquo;Captain or nothing&rdquo; — it is &ldquo;Captain or build it ourselves&rdquo; or &ldquo;Captain or this neighboring product.&rdquo; Here is how the field lines up.</p>
<table>
  <thead>
      <tr>
          <th>Option</th>
          <th>What It Is</th>
          <th>Best For</th>
          <th>Watch Outs</th>
      </tr>
  </thead>
  <tbody>
      <tr>
          <td><strong>Captain</strong></td>
          <td>Managed, self-tuning RAG API</td>
          <td>Production agents that need deterministic, current retrieval without infra upkeep</td>
          <td>SaaS trust concern; credit-based cost for heavy multimodal loads</td>
      </tr>
      <tr>
          <td><strong>DIY RAG</strong> (LangChain + vector DB)</td>
          <td>Assembled pipeline teams maintain</td>
          <td>Full control and customization</td>
          <td>Continuous chunking/embedding/re-indexing burden; &ldquo;spotty RAG&rdquo; reliability</td>
      </tr>
      <tr>
          <td><strong>Google Vertex File Search</strong></td>
          <td>Closest managed incumbent</td>
          <td>Teams already in GCP</td>
          <td>Tighter coupling to Google ecosystem</td>
      </tr>
      <tr>
          <td><strong>Glean / Onyx / Sana</strong></td>
          <td>End-user knowledge assistants</td>
          <td>Human chat UX over many apps</td>
          <td>Not built as a raw retrieval API for agents</td>
      </tr>
      <tr>
          <td><strong>OpenSearch</strong></td>
          <td>Low-level search engine</td>
          <td>Teams that want to own the engine</td>
          <td>No managed retrieval workflow out of the box</td>
      </tr>
      <tr>
          <td><strong>Ragie</strong></td>
          <td>Hosted RAG service</td>
          <td>Former hosted-RAG customers</td>
          <td>Shut down 19 July 2026; migrating users to Captain</td>
      </tr>
  </tbody>
</table>
<p>Founders explicitly cite Google Vertex File Search as the main similar product, while distinguishing OpenSearch as a low-level engine and Glean/Onyx/Sana as end-user assistants rather than agent-facing APIs. Captain&rsquo;s positioning, therefore, is narrow but deliberate: the retrieval backend behind your agent, not yet another chat UI.</p>
<h2 id="the-ragie-shutdown-and-hosted-rag-consolidation">The Ragie Shutdown and Hosted-RAG Consolidation</h2>
<p>In a market already crowded with hosted-RAG vendors, the clearest signal for 2026 came from a competitor&rsquo;s failure. Ragie, a competing hosted RAG service that served many teams who did not want to build retrieval in-house, shut down on 19 July 2026. Ragie publicly directed its customers to migrate — and several of them landed on Captain.</p>
<p>The migration mechanics matter for anyone evaluating lock-in. Captain&rsquo;s migration path lets you connect the original source (S3, Google Drive, GCS, or Dropbox) directly, with no need to move data through Ragie first; most customers with existing access were set up in under 15 minutes. This is a direct competitive win and a consolidation proof point: even funded hosted-RAG startups are not immune to shutdown, which raises the stakes on picking a vendor with apparent staying power and a low-friction migration story.</p>
<p>For evaluators, the lesson cuts both ways. The hosted-RAG niche is proving volatile, and a vendor&rsquo;s financial durability is part of the risk equation along with its features.</p>
<h2 id="performance-and-tech-v2-the-3x-latency-cut-and-object-storage-embeddings">Performance and Tech: v2, the 3x Latency Cut, and Object-Storage Embeddings</h2>
<p>Captain&rsquo;s v2 API, declared stable on 3 January 2026, came with a new docs site (docs.runcaptain.com), an interactive playground, and Python and TypeScript SDKs. The most technically interesting claim is the infrastructure choice behind its performance.</p>
<p>Captain reports a 3x drop in search latency after migrating embeddings to object storage instead of a vector database, alongside better recall. This runs counter to the orthodoxy that a dedicated vector database is mandatory for production RAG. For many workloads, object storage plus the right query path and BM25 blend can beat a vector DB on both latency and cost.</p>
<p>Two design decisions explain the recall gains:</p>
<ol>
<li><strong>Long-context document embedding</strong> — entire-file context combined with narrow chunks, so embeddings capture document-level meaning rather than isolated fragments.</li>
<li><strong>Automatic domain detection feeding BM25</strong> — fixes &ldquo;lost&rdquo; domain-specific terms such as drug names and non-English legal terminology that pure vector search tends to miss.</li>
</ol>
<p>Captain also emphasizes precision optimization for healthcare, legal, and financial use cases, and partnered with the HN team to build RAG forum search over 19+ years of posts. Citations are part of the trust story: deterministic page-number citations for PDFs, with exact bounding-box citations coming, and citations linked to source object storage.</p>
<h2 id="pros-and-cons-of-captain-for-teams">Pros and Cons of Captain for Teams</h2>
<h3 id="pros">Pros</h3>
<ul>
<li><strong>Deterministic, sub-second search API</strong> designed for agents, with filters and re-ranking.</li>
<li><strong>Self-tuning evaluation loop</strong> via <code>captain_eval</code> and MCP triggers reduces manual RAG tuning.</li>
<li><strong>Multimodal extraction</strong> covers scans, handwriting, tables, screenshots, audio, and video — well beyond plain-text RAG.</li>
<li><strong>Transparent, published pricing</strong> with a genuine free Developer tier.</li>
<li><strong>Proven migration path</strong> with data pulled directly from the original source.</li>
<li><strong>SOC 2 Type II, GDPR, and HIPAA</strong> compliance claims as of 2026.</li>
<li><strong>Interesting infra bet</strong> (object-storage embeddings) that challenges the &ldquo;vector DB is mandatory&rdquo; assumption.</li>
</ul>
<h3 id="cons">Cons</h3>
<ul>
<li><strong>SaaS trust concern</strong> for sensitive documents with a young YC startup; critics questioned &ldquo;vibe auditing&rdquo; as a substitute for rigorous SOC 2 verification.</li>
<li><strong>Credit-based cost</strong> can climb for heavy video, audio, or advanced-processing workloads.</li>
<li><strong>&ldquo;Few months-years early&rdquo;</strong> for optimization-focused buyers, per HN skepticism.</li>
<li><strong>Narrower positioning</strong> than all-in-one knowledge assistants; it is a retrieval API, not a chat UX.</li>
</ul>
<h2 id="is-captain-worth-it-in-2026-verdict">Is Captain Worth It in 2026? Verdict</h2>
<p>Captain is worth serious evaluation if your team is building AI agents that need reliable, current retrieval over company files and you do not want to own the full RAG maintenance burden. The self-tuning loop, multimodal processing, and object-storage latency bet address real pain — especially the &ldquo;spotty RAG&rdquo; problem that is the top reliability complaint in production retrieval.</p>
<p>The counter-argument from HN skeptics is honest and should be weighed: you can already &ldquo;talk to files&rdquo; with Gemini or vibe-code a pipeline, and for sensitive documents, trusting a young hosted SaaS vendor carries real risk. The Ragie shutdown is a live reminder that even well-meaning hosted-RAG vendors disappear.</p>
<p>Given the free Developer tier, the cheapest way to resolve the debate is empirical: point Captain at a representative slice of your files, run your own queries, and compare precision and latency against your current setup over a week. If deterministic citations and reliable retrieval save your team the hours they currently spend babysitting a home-grown index, the subscription pays for itself. If your workload is small or your documents are too sensitive to leave the network, the free tier and enterprise SOC 2/HIPAA options still give you a low-risk way to scope it before committing.</p>
<h2 id="faq">FAQ</h2>
<h3 id="what-is-captain-rag-for-files">What is Captain RAG for files?</h3>
<p>Captain is an API-first, self-tuning retrieval platform from YC W26 that indexes cloud storage and SaaS sources into one queryable index behind a single query API for AI agents. It automates chunking, embedding, re-ranking, permissions, and continuous re-indexing.</p>
<h3 id="how-much-does-captain-cost-in-2026">How much does Captain cost in 2026?</h3>
<p>Captain offers a free Developer plan (500 credits, 1,000 queries/mo), a $1,600/mo Startup plan with 83,000 credits and unlimited queries, and custom Enterprise pricing. Credit rates range from $0.02/page for text to $0.40/min for video.</p>
<h3 id="what-happened-to-ragie-and-how-does-it-relate-to-captain">What happened to Ragie and how does it relate to Captain?</h3>
<p>Ragie, a hosted RAG service, shut down on 19 July 2026, and many of its customers migrated to Captain. The migration connects the original data source directly, with most setups completed in under 15 minutes.</p>
<h3 id="does-captain-use-a-vector-database">Does Captain use a vector database?</h3>
<p>No — Captain&rsquo;s v2 moved embeddings to object storage instead of a vector database, reporting a 3x search-latency reduction and better recall. It blends vector search with BM25 keyword retrieval and automatic domain detection.</p>
<h3 id="is-captain-compliant-with-security-standards">Is Captain compliant with security standards?</h3>
<p>Captain claims SOC 2 Type II, GDPR, and HIPAA compliance as of 2026, with secure handling, backups, and 24/7 monitoring. However, some HN commenters questioned the rigor of its compliance auditing for a young startup.</p>
]]></content:encoded></item></channel></rss>