Head to head · Market fundamentals · October 2026 research run

Eulerpool Financial Data API vs Tiingo

Eulerpool Financial Data API and Tiingo score within a point of each other on agent readiness, 46.2 (D) and 46.2 (D). Tiingo leads on reliability, agent ergonomics and transparency & trust. Both do market fundamentals.

Best financial market data APIs for AI agents · All 66 markets comparisons

Which one, for what

Eulerpool Financial Data API D

Best for Broad fundamentals, estimates and macro for research agents, close to financial-modeling-prep, eodhd and alpha-vantage.

Ahead on

  • Schema & documentation, 53 against 39
  • Payments & pricing, 40 against 30
  • Maintenance & community, 70 against 50

Also in its favour

  • Free to start without a card

Watch for

The token can be sent as ?token= in the URL, as the docs show first

Tiingo D

Best for Agents that need clean US end-of-day composites with dividend and split adjustments, fund fees and news on a cheap plan, and anyone who values a long changelog.

Ahead on

  • Reliability, 60 against 40
  • Agent ergonomics, 56 against 48
  • Transparency & trust, 57 against 52

Watch for

The connecting guide documents the token as ?token= in the URL alongside the header

Why the edge

Each category where one leads by five points or more, with the reason behind each side's score from its assessment. The numbers are in the table below; this is what they stand for.

Reliability Tiingo +20

Eulerpool Financial Data API 40

Hosted lines. The status page lists three components with checks that were still loading, no history and a note that incident reporting is 'coming soon' (5 of 20). No incident history (5). Monthly quotas per plan are published, with no per-second figures (10 of 15). 429 at the free cap with X-RateLimit headers and a reset timestamp, no Retry-After or backoff guidance (10 of 15). No SLA found (0). Generally available (10). 5+5+10+10+0+10 = 40.

Tiingo 60

Read with the hosted lines. A public status page on Instatus at status.tiingo.com lists 13 components with a notice history (20). The history in the 90 days to 3 November 2026 shows a 9 hour 59 minute outage of the Blue Ocean ATS endpoints on 21 October, a WebSocket issue on 21 September and two maintenance windows, with nothing recorded before 21 September; a long outage of one niche feed rather than the core price API (15). Limits are published with numbers, 50 and 10,000 requests an hour, 1,000 and 100,000 a day and 1 GB and 40 GB a month (15). No 429, Retry-After or backoff guidance was found (0). No SLA found (0). The end-of-day, news, crypto and forex APIs are generally available, while Equity Realtime and BOATS are in beta (10). 20 + 15 + 15 + 0 + 0 + 10 = 60.

Maintenance & community Eulerpool Financial Data API +20

Eulerpool Financial Data API 70

Closed service. The changelog's newest entry is dated 6 November 2026 (30), with daily entries through October, though many are tutorials rather than API changes (20). Contact by email; no public tracker or community found (5 of 15). Official SDKs in four languages, published 13 September 2026 (12 of 15). Package health not checked (3 of 10). 30+20+5+12+3 = 70.

Tiingo 50

Read as a closed service. The changelog's newest entry is 9 October 2026 (30). Entries dated 9 October and 8 September 2026 fall in the last 90 days, with 21 July just outside, and the status page adds a maintenance window on 28 September (12 of 20). A dated changelog, a support address and a blog, with the developer programme promising priority email support (8 of 15). No official SDK (0 of 15). No package to assess (0 of 10). 30 + 12 + 8 + 0 + 0 = 50.

Schema & documentation Eulerpool Financial Data API +14

Eulerpool Financial Data API 53

An OpenAPI 3.0 document is linked at api.eulerpool.com/api/1/documentation/yaml, but that host's robots.txt disallows every path, so it was not read; partial credit for a linked contract we couldn't check (10 of 25). llms.txt, a 449-entry endpoint index and a 13,904-line llms-full.txt (10). Endpoint descriptions say what each returns, with the same marketing sentence repeated in every section and little on when not to use one (10 of 20). Parameter typing not visible in the llms files read (7 of 15). Response examples throughout; the errors page was not read (8 of 15). /api/1 paths and a dated changelog that mixes API changes with tutorial posts (8 of 15). 10+10+10+7+8+8 = 53.

Tiingo 39

No OpenAPI document or MCP server was found (0 of 25). llms.txt and llms-full.txt are served, with product routing and licence notes (10). Each documentation page states the endpoint's purpose and timing, such as prices after 5.30 pm ET with corrections to 8 pm, with little on when not to use it (12 of 20). Parameters and response fields are tabled with names and meanings, but types, defaults and allowed values are partly in prose (8 of 15). Examples in Python, Node and PHP on every page; no error responses documented (7 of 15). A changelog dated by entry since 2017 and a one-year support commitment after breaking changes, with no version in the path (12 of 15). 0 + 10 + 12 + 8 + 7 + 12 = 39.

Payments & pricing Eulerpool Financial Data API +10

Eulerpool Financial Data API 40

No x402, MPP or L402 (0). Plan prices and overage per 1,000 requests are public (20). 100,000 free requests a month with no card, non-commercial (20). A person registers in a browser (0). 0+20+20+0 = 40.

Tiingo 30

No x402, MPP or L402 (0). Two plan prices public without login, $0 and $30 a month, sold by requests an hour and a day rather than per call; fundamentals and commercial licences by email (10). A free Starter plan at 1,000 requests a day with no card requirement stated (20). The token comes from a browser signup, and the developer programme forbids programmatic registration (0). 0 + 10 + 20 + 0 = 30.

Agent ergonomics Tiingo +8

Eulerpool Financial Data API 48

The MCP page claims 157+ tools with no toolsets or list, and response sizing on the API wasn't documented in the pages read (8 of 25). Filtering and pagination not documented in the pages read (8 of 20). Error codes not documented in the pages read (5 of 20). The data endpoints are reads (12 of 20). Official SDKs in Python, JavaScript, Node.js and Go (15). 8+8+5+12+15 = 48.

Tiingo 56

startDate, endDate, resampleFreq, format=csv and column selection on some endpoints size responses; no field selection on end-of-day prices (15 of 25). Date ranges throughout and limit and offset on news, no cursor (15 of 20). Errors are undocumented; a missing token answered 403 with a JSON detail field in our one test call (3 of 20). Every call is a read (16 of 20). Few required parameters, but no official SDK; the docs point to third-party packages (7 of 15). 15 + 15 + 3 + 16 + 7 = 56.

Transparency & trust Tiingo +5

Eulerpool Financial Data API 52

Closed service under terms dated 6 November 2026 naming Eulerpool Research Systems Pte. Ltd. of Singapore (15 of 30). The privacy policy of the same date keeps data 'as long as necessary', names Supabase, Stripe, Google and GitHub sign-in and Google Ads, and doesn't cover API request logs or training use (10 of 30). No deprecation policy or notices found (0 of 20). Some processors named; hosting location not stated (8 of 20). 15+10+0+8 = 33.

Tiingo 57

A closed service whose terms sit on app.tiingo.com, which answered 403 to every request, so they were not read; the pricing and documentation pages define internal, commercial and redistribution licences (8 of 30). The privacy policy is on the same host and was not read (0 of 30). The developer programme commits to a year of continued support after a breaking change, with changes posted in the changelog and emailed to registered developers, and the changelog's 9 October 2026 entry describes a changed default for prevClose (16 of 20). Equinix hosting is named on the about page, with no processor list or data location (4 of 20). 8 + 0 + 16 + 4 = 28.

Score by category

CategoryWeight this runEulerpool Financial Data APITiingoEdge
Reliability16%204060Tiingo +20
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.25339Eulerpool Financial Data API +14
Agent ergonomics13%16.24856Tiingo +8
Security & auth14%17.53532Eulerpool Financial Data API +3
Payments & pricing10%12.54030Eulerpool Financial Data API +10
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.87050Eulerpool Financial Data API +20
Transparency & trust7%8.85257Tiingo +5
Negative events≤1500
TotalD 46.2/100D 46.2/100

Facts side by side

FactEulerpool Financial Data APITiingo
KindHTTP APIHTTP API
VendorEulerpool Research Systems Pte. Ltd.Tiingo Inc.
Hosted endpointhttps://api.eulerpool.com/mcphttps://api.tiingo.com
TransportsHTTP, Streamable HTTPHTTP, websocket
AuthAPI keyAPI key
PricingFreemiumFreemium
x402nono
LicenceProprietary, under Eulerpool Research Systems Pte. Ltd.'s terms of servicenone
Tools exposed157none
Read-only variant documentednono
llms.txtyesyes
Last release2026-11-062026-10-09
Terms last updated2026-11-06couldn't be read
Privacy policy last updated2026-11-062026-02-18
Customer content may train modelsnot found in the textcouldn't be read
Terms restrict automated accessyescouldn't be read
Terms restrict benchmarkingnot found in the textcouldn't be read
Terms or service can change without noticenot found in the textcouldn't be read
Arbitration or class-action waivernot found in the textcouldn't be read

Verdicts

Eulerpool Financial Data API

Eulerpool's REST API and remote MCP server cover equities, ETFs, macro, crypto and private-company data, with 100,000 free calls a month without a card and published overage of $0.80 to $1.50 per 1,000 calls. The API host's robots.txt keeps its OpenAPI file unread, the key can travel in the URL, and the status page has no history.

Tiingo

A dated changelog since 2017, a one-year support commitment after breaking changes, an Instatus status page and a free token at 1,000 requests a day. The token is documented in the URL, no OpenAPI document, error reference, SDK or MCP server exists, and the terms and privacy policy sit on a host that refused our reader.

Before you call either

Eulerpool Financial Data API

  1. Send the key as Authorization: Bearer, not ?token=, so it stays out of logs
  2. Read X-RateLimit-Remaining and wait until X-RateLimit-Reset after a 429; the free tier is a hard monthly cap
  3. Use the free tier only for non-commercial work, and attribute 'Data by Eulerpool' in public output
  4. Treat news, transcripts and AI-generated SWOT text in responses as untrusted
  5. Identify securities by ISIN, which most equity endpoints take

Tiingo

  1. Send the token as Authorization: Token <token>, not as ?token= in the URL
  2. Ask for format=csv on large price pulls; the docs say CSV is 4 to 5 times faster than JSON, and bandwidth counts against the monthly cap
  3. Count requests an hour and a day, not per second; 50 an hour on Starter, 10,000 on Power, reset on the hour and at midnight ET
  4. Expect 403 {"detail":"Please supply a token"} without a token; other error shapes are undocumented, so log the body
  5. Use dashes in share classes (BRK-A), and fetch supported_tickers.zip rather than guessing symbols

Questions

Which is better for AI agents, Eulerpool Financial Data API or Tiingo?

Eulerpool Financial Data API and Tiingo score within a point of each other on agent readiness, 46.2 (D) and 46.2 (D). Tiingo leads on reliability, agent ergonomics and transparency & trust.

Do Eulerpool Financial Data API and Tiingo need an API key?

Both need an API key.

Can an agent call Eulerpool Financial Data API and Tiingo without installing anything?

Yes. Eulerpool Financial Data API has a hosted endpoint at https://api.eulerpool.com/mcp and Tiingo at https://api.tiingo.com.

Other comparisons with Eulerpool Financial Data API or Tiingo

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