Launched this week
Castling Financial
Source of truth SEC filing data for humans and AI
19 followers
Source of truth SEC filing data for humans and AI
19 followers
Castling Financial turns SEC EDGAR filings into tools humans and AI can actually use, at a low cost. Browse a research dashboard with statements, charts, and provenance on every figure. Ask Castle AI filing-grounded questions. Connect via MCP so GPT, Claude, and other agents pull the same SEC-traceable data. Built for accuracy: reported values map back to filing tags and accessions. If it is not in the filing path, it stays blank. No silent vendor estimates. Data humans and AI agents can trust
Hey Product Hunt. I’m Zac, founder of Castling Financial.
I built this because consumer finance sites (Yahoo Finance, Google Finance, and similar) are fine for a quick glance, but they’re often opaque, sometimes wrong or delayed, and the UIs feel stuck in another decade. “AI for finance” tools have the same trust problem: they sound confident and can’t show where a number came from.
Castling starts from SEC EDGAR / XBRL filings and keeps a paper trail. Humans get a cleaner research dashboard with statements, charts, and provenance on figures, along with Castle AI assistant. AI agents get MCP so GPT, Claude, Cursor, and others can pull the same SEC-traceable data. Structured MCP tool results typically use far fewer tokens than pasting scraped pages into the model. In practice we often see roughly 10-20x less context (and cost) than scrape-heavy workflows. That is an observed order of magnitude, not a guarantee for every prompt. Moreover, it's more accurate than using a tree sitter. A tree walk still depends on finding the right node and reading text/tables, which models (and scrapers) can misread.
What you can try today:
Company dashboard built for research, not ad clutter
Provenance on figures (filing / tag trail when present)
Castle AI + MCP for agent workflows
What it is not: live quotes, Street estimates, or inventing missing tags. If it isn’t in the filing path, it stays blank.
Would love feedback from PH, especially:
Is the dashboard clearer than the usual finance portals?
Is provenance obvious on first use?
What’s missing for MCP / agent builders?
Happy to answer anything in the comments. I'll be around :D
Love that every number ties back to the original filing tag, that provenance layer is exactly what's missing from most financial tools. One thing I'd want: a simple diff view between two filings of the same company so you can quickly spot which line items changed quarter over quarter without scrolling through both 10-Qs manually.
@birgl1s2z Hey, Birgül! Thank you for the comment! Love hearing this. That provenance layer is the thing I care about most, every figure back to the filing tag. And yes, will definitely add a simple filing-to-filing diff so you can spot what moved without spelunking two 10-Qs. Really good call. It’s high on my list. Thanks for pushing on it.
Love that every figure ties back to the original filing tag, that provenance layer is the kind of trust signal most tools skip. One thing that would make this even more useful for me: let me save a custom watchlist of tickers and get a digest when a new 10-Q or 8-K lands, with Castle AI pre-summarizing the deltas against the prior quarter. Would save a lot of tab refreshing during earnings season.
@fcalapverd79575 Hey Funda, thank you for the comment and feedback! I will definitely add that in as a feature. I'm glad you like the provenance layer!
Finally something built for verifiable accuracy, love that blank values stay blank instead of being filled with vendor estimates. The MCP hookup to GPT was smoother than I expected, pointed it at a 10-K and the answers came back tagged straight to the filing.
@avcarnecde70934 Hey Necdet, this made my day! Thank you. Blank staying blank (instead of fake “complete” estimates) is the whole thesis. So glad the MCP → GPT path felt smooth, and that the answers came back tagged straight to the 10-K. That’s exactly what I built it for.
The MCP setup was the standout for me, hooked it into Claude and it pulled only what was directly traceable to the filings rather than guessing. Really appreciate seeing the accession number right next to every number in the dashboard.
@cuma59h2 Hey Cuma! Thank you for the comment! So glad that stood out. MCP into Claude was a big focus for me. Thrilled you saw the value of having accession numbers right next to every number. Really glad the whole setup clicked for you.
Plugged it into Claude and asked about a mid-cap's revenue trends, the answers came back straight from the filing with the accession right there. That provenance thing is genuinely useful, not just a nice-to-have.
@blent457193 Hey, Bülent! Thank you for the comment. Small/Mid-caps is definitely one of the places where I care about Castling most, honestly. Mega caps are everywhere. The smaller names are the ones where data gets thin, estimates sneak in, and it’s hard to tell if a number is real. Being able to ask Claude about a mid-cap’s revenue and get answers straight from the filing, with the accession right there, is the whole point. Glad that provenance actually helped. Thanks for trying it on a name that isn’t just another large cap!
The provenance trail on every figure is exactly the kind of unglamorous, disciplined work that makes financial data actually usable. Glad someone finally drew the line at silent estimates.
@demirleng78497 Hey Zübeyde! Thank you for the comment! This is the nicest way anyone’s put it. That “draw the line at silent estimates” choice is core Castling. Unglamorous, disciplined, and (I think) what makes the data actually usable and more trustworthy than any other source. So glad it resonated!