Who it is for
Tax preparers and product teams that need computed returns rather than guidance.
Aiwyn Tax (formerly Column Tax)
US federal and state tax calculation with a 1040 PDF back
Overview
What Aiwyn Tax (formerly Column Tax) does
Aiwyn Tax, formerly Column Tax, exposes a tax calculation engine. The workflow its tools imply is schema-first: list supported tax years and jurisdictions, ask which input namespaces exist for a jurisdiction, fetch the JSON schema for a namespace such as irs1040, irs1040_schedulec, or ca_form540, then submit input conforming to that schema for validation and calculation. PDF generation is asynchronous, started by one call and collected by another once the job reports complete. The listing describes handing over source documents such as W-2s and receiving a finished 1040 in return.
Tool surface
The surface is a schema-driven calculation pipeline: `tax_simple_return` to orient, `tax_namespaces` and `tax_namespace_schema` to discover the input shape, `check_tax` then `calculate_tax` to validate and compute, and a two-step `generate_tax_pdf_tool` and `get_tax_pdf_tool` pair for output. Ten tools answered against nine claimed, the extra being a `generate_uuid_v5` helper.
Availability
Where Aiwyn Tax (formerly Column Tax) is listed
Aiwyn Tax (formerly Column Tax) is listed in the Claude connectors directory only. Aiwyn, Inc. has no app under the same domain in the ChatGPT directory; 392 of the 3,150 products here are on both marketplaces, and this is not one of them.
The MCP server behind a Claude connector is usually the same server a ChatGPT app would need, so the absence is a distribution decision rather than a technical one.
Claude listing
In the Claude connectors directory
Aiwyn Tax (formerly Column Tax) publishes 9 tools to Claude. That is a mid-sized surface: 41.3% of the 1,253 Claude-listed connectors expose fewer.
The median Claude-listed connector filed under Finance publishes 12, so this one sits 3 tools below its bucket's median, 95th of 159.
It falls in the 7-10 tools band, which holds 14.6% of the Claude directory.
Measured against the live endpoint
A direct call to the endpoint returned 10 tools, 1 more than the 9 the listing publishes. Probed 2026-08-07.
Tools the server actually returns
check_taxcalculate_taxtax_yearstax_jurisdictionstax_namespace_schematax_namespacestax_simple_returngenerate_tax_pdf_toolget_tax_pdf_toolgenerate_uuid_v5
Aiwyn Tax (formerly Column Tax) publishes a remote MCP endpoint. Claude connects to it over HTTP; there is nothing to install locally.
Every connector in the Claude directory is remote, all 1,253 of them, so transport is not a differentiator there.
- Publisher
- Aiwyn, Inc.
- Verification
- Verified partner (37.8% of the Claude directory)
- Filed under
- Financial Services
- Endpoint
-
https://mcp.columnapi.com/mcp - Documentation
- Publisher setup docs
- Published tools
- 9 · 7-10 tools band
- Depth rank in Finance
- 95 of 159
- Snapshot
- August 2026
Aiwyn Tax (formerly Column Tax) carries partner verification in the Claude directory, which 474 of 1,253 listings do (37.8%). That is a review step past self-publishing, not an Anthropic-built server.
In the publisher's words
How Aiwyn, Inc. describes it
Estimate your federal & state taxes using Aiwyn's tax engine that's filed over 1 million returns. Give Claude your tax documents (e.g. W-2s) and get a 1040 PDF back.
Quoted from the connector's own Claude directory listing as captured in August 2026. Node8 did not write it and does not vouch for it.
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This is an independent catalogue entry compiled by Node8 from Aiwyn Tax (formerly Column Tax)'s public marketplace listing as it stood in August 2026. Listing facts come from the marketplaces; the comparisons against the rest of the directory and any live-endpoint measurements are Node8's. Node8 is not affiliated with Aiwyn, Inc., and inclusion here is not an endorsement.
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