{ "data": { "a": { "slug": "fonoa", "name": "Fonoa", "vendor": "Fonoa Technologies Limited", "vendorUrl": "https://www.fonoa.com", "kind": "http-api", "category": "tax", "summary": "Fonoa is a hosted indirect tax platform for VAT, GST and sales tax. Its REST API validates tax identification numbers, calculates tax on a transaction and reports e-invoices to tax authorities, with a sandbox and a demo environment.", "url": "https://www.anchorterminal.com/tools/fonoa", "markdownUrl": "https://www.anchorterminal.com/tools/fonoa.md", "slimMarkdownUrl": "https://www.anchorterminal.com/tools/fonoa.min.md", "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/fonoa.json", "license": "Proprietary service. The API contract is not published. The public Terms of Service took effect on 14 May 2020 and name older seller sites", "transports": [ "http" ], "remoteUrl": "https://api.fonoa.com", "packages": [], "auth": "api-key", "authNotes": "Every request needs a subscription key in the `Ocp-Apim-Subscription-Key` header. Fonoa issues a primary and a secondary key once a client is onboarded, on request by email or through the sales form, with separate keys for the sandbox and production. No self-serve key page, scopes, read-only keys or expiry were found in the docs. Countries are enabled per tenant, and a call for a country that is not enabled returns `COUNTRIES_NOT_ALLOWED`. Webhooks are set up by asking a Fonoa contact.", "pricing": "paid", "pricingNotes": "No public prices. www.fonoa.com/pricing returns 404 and the site's buttons read \"Get in touch\". No free tier or self-serve trial was found. The sandbox has unlimited usage with fixed data and the demo environment has limited usage, and a key for either comes from Fonoa after contact (https://docs.fonoa.com/reference/environments, checked 2026-10-08).", "priceSummary": "Paid", "where": "hosted", "x402": { "level": "no", "evidence": "No x402, MPP or L402 in the API docs, the OpenAPI definitions or the website (checked 2026-10-08).", "endpoints": [] }, "toolCount": null, "popularity": { "githubStars": null, "npmWeekly": null, "pypiWeekly": null, "asOf": "2026-10-08" }, "docsUrl": "https://docs.fonoa.com", "llmsTxt": "https://docs.fonoa.com/llms.txt", "capabilities": [ "tax.calculate", "tax.transactions", "tax.invoicing" ], "tags": [ "hosted", "paid", "closed-source", "api-key", "openapi", "llms-txt", "sandbox", "webhooks", "sales-led", "status-page", "iso27001" ], "lastRelease": "2026-10-02", "graded": true, "anchor": { "graded": true, "score": 51.7, "grade": "D", "agentReady": false, "rank": 575, "ranked": true, "rankOf": 722, "categoryRank": 8, "methodology": "0.4", "run": "2026-10-01", "scores": { "ergonomics": 64, "maintenance": 49, "payments": 3, "reliability": 66, "schema": 68, "security": 47, "transparency": 48 }, "pending": [ "performance", "tasks" ], "assessment": { "confidence": "medium", "date": "2026-10-08" }, "negative": 0, "verdict": "The API reference is served as Markdown with an OpenAPI definition on each endpoint page, and e-invoicing submissions are idempotent by `transaction_id`. API keys are issued by Fonoa staff after contact, no price, rate limit or changelog is published, and the only public terms date from May 2020 and cover older seller sites.", "bestFor": "An agent working for a company that already has a Fonoa contract and needs tax ID validation, VAT or GST calculation, or e-invoice reporting across many countries through one API.", "strengths": [ "Every reference page is served as Markdown with its OpenAPI 3.0 definition inline, indexed by docs.fonoa.com/llms.txt", "E-invoicing submissions are idempotent by `transaction_id`, and the docs say a transaction can be replayed any number of times", "The sandbox at sandbox.fonoa.com returns fixed outcomes for documented test inputs, including errors, delays and HTTP 500", "Webhooks carry a signed OIDC token with a SHA-256 checksum of the body, valid for one hour", "status.fonoa.com shows 100 per cent over 90 days for its E-Invoicing, Lookup and Tax monitors on 8 October 2026" ], "weaknesses": [ "No self-serve signup. Sandbox, demo and production keys are issued by Fonoa after contact by email or the sales form", "No pricing page. www.fonoa.com/pricing returns 404 and the site's buttons read \"Get in touch\"", "No rate limit numbers found. The 429 response says \"Try again a bit later\" with no `Retry-After` documented", "No changelog, deprecation policy, official SDK or MCP server found. docs.fonoa.com/changelog returns 404", "The only public terms took effect on 14 May 2020 and cover older seller sites. They bar benchmarking and automated access without written permission" ], "agentNotes": [ "Send the key in the `Ocp-Apim-Subscription-Key` header. Use the sandbox key at https://sandbox.fonoa.com and the production key at https://api.fonoa.com", "Treat validations and e-invoicing submissions as asynchronous. POST, then poll the GET endpoint or wait for the webhook, and avoid tight polling", "Reuse the same `transaction_id` on a retry of `/v1/transactions`. A transaction already processed is not processed again", "Commit a calculation with POST `/tax/v2/calculations/\u003cuuid\u003e/commit` only when the sale is final. The commit adds it to revenue tracking", "Ask the Fonoa contact to configure webhooks. There is no API for it, and always fetch `resource_url` as given in the webhook" ], "metrics": { "kind": "remote", "measured": false }, "reviewCount": 0, "avgRating": 0, "history": [ { "basis": "public evidence", "confidence": "medium", "grade": "D", "methodology": "0.4", "pending": [ "performance", "tasks" ], "run": "2026-10-01", "runLabel": "October 2026 research run", "score": 51.7 } ], "editorialScores": { "ergonomics": 64, "maintenance": 49, "payments": 3, "reliability": 66, "schema": 68, "security": 47, "transparency": 27 }, "provenanceScore": 69 }, "connect": { "http": "curl --location 'https://sandbox.fonoa.com/lookup/v2/single-validations' \\\n--header 'Content-Type: application/json' \\\n--header 'Ocp-Apim-Subscription-Key: \u003cyour-sandbox-API-key\u003e' \\\n--data '{\n \"country_iso_code\": \"pl\",\n \"tax_identification_number\": \"2000\"\n}'" }, "letme": { "capability": "https://letme.dev/tax.calculate", "tool": "https://letme.dev/fonoa" }, "area": "domain-data", "provenance": { "legalEntity": "Fonoa Technologies Limited", "domain": "fonoa.com", "domainRegistered": "2004-08-24", "endpointOnVendorDomain": true, "terms": "", "privacy": "https://www.fonoa.com/legal/privacy-notice", "statusPage": "https://status.fonoa.com", "changelog": "", "securityTxt": "none", "checked": "2026-10-08", "notes": [ "The privacy notice names Fonoa Technologies Limited, 6th Floor, South Bank House, Barrow Street, Dublin 4, Ireland as data controller. The site footer gives Irish company number 677236.", "No terms URL is recorded. The only terms Fonoa publishes, at www.fonoa.com/legal/terms-of-service, took effect on 14 May 2020, apply to fonoatech.com, efacturacion.net, efiscal.biz, portugal.fonoatech.com and efatture.net, name Fonoa Technologies ltd. and are governed by Croatian law. No service agreement or API terms for fonoa.com customers were found.", "The privacy notice says it does not apply to personal data Fonoa processes on behalf of customers using its software, where Fonoa is a processor under the customer's contract. No date of last update was found on the page.", "The API answers at api.fonoa.com, sandbox.fonoa.com and api-demo.fonoa.com, all on the vendor's domain.", "www.fonoa.com/.well-known/security.txt and www.fonoa.com/security.txt return 404. The security page describes a vulnerability disclosure programme with an email address.", "No changelog was found. docs.fonoa.com/changelog returns 404, and product news is published as blog posts.", "RDAP for fonoa.com gives a registration date of 2004-08-24." ], "score": 69 }, "pageJsonUrl": "https://www.anchorterminal.com/tools/fonoa.json", "live": { "slug": "fonoa", "probe": { "target": "https://api.fonoa.com", "method": "get", "lastAt": "2026-10-08T21:12:10.772964244Z", "lastOk": true, "lastStatus": 404, "lastMs": 63, "authRequired": false, "uptime24h": 100, "uptime30d": 100, "p50ms24h": 99, "p95ms24h": 161, "samples24h": 21, "samples30d": 21, "days": [ { "date": "2026-10-08", "probes": 21, "ok": 21 } ] }, "vendorStatus": { "page": "https://status.fonoa.com", "indicator": "unknown", "summary": "no machine-readable status found", "checkedAt": "2026-10-08T19:38:33.601208747Z" }, "updatedAt": "2026-10-08T21:12:10.772964244Z" } }, "answer": "Fonoa scores 51.7 (D) on agent readiness against Numeral's 49.3 (D), and leads in 2 of 7 scored categories. Numeral leads on schema \u0026 documentation, agent ergonomics, payments \u0026 pricing and maintenance \u0026 community.", "b": { "slug": "numeral", "name": "Numeral", "vendor": "Numeral Two, Inc.", "vendorUrl": "https://www.numeral.com", "kind": "http-api", "category": "tax", "summary": "Numeral is a hosted sales tax and VAT compliance service from Numeral Two, Inc. Its REST API calculates tax, records transactions and refunds, and manages exempt customers, and Numeral registers and files. A remote MCP server reads the account.", "url": "https://www.anchorterminal.com/tools/numeral", "markdownUrl": "https://www.anchorterminal.com/tools/numeral.md", "slimMarkdownUrl": "https://www.anchorterminal.com/tools/numeral.min.md", "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/numeral.json", "repo": "https://github.com/NumeralHQ/numeral-tax-go", "license": "Proprietary service under Numeral's terms of service. The Go, Python and Node SDKs are Apache-2.0", "transports": [ "http", "streamable-http" ], "remoteUrl": "https://api.numeralhq.com", "packages": [ { "registry": "go", "name": "github.com/NumeralHQ/numeral-tax-go" }, { "registry": "pypi", "name": "numeral-tax" }, { "registry": "npm", "name": "numeral-tax" } ], "auth": "api-key", "authNotes": "The API and the MCP server take a secret API key as a Bearer token, `sk_test_` for the sandbox or `sk_prod_` for live data. Keys are created and revoked in the dashboard at dashboard.numeralhq.com under Developers. No scopes, expiry or OAuth flow were found, and publishable keys are rejected by the MCP server. Dashboard access starts with the get-started form or a demo, and the product page says to book a demo before generating test keys. MCP write tools are enabled per account on request.", "pricing": "paid", "pricingNotes": "Professional is $75 per filing and $150 per state registration, month to month. The tax engine and API are listed under Enterprise at a custom price. Monitoring (nexus study and alerts) is free. Test keys record transactions with no charges or remittance, but no self-serve signup was found and whether a free account can create keys isn't stated (https://www.numeral.com/pricing, checked 2026-10-08).", "priceSummary": "$75 / tx", "where": "hosted", "x402": { "level": "no", "evidence": "No x402, MPP or L402 in the API docs, the OpenAPI spec or the pricing page (checked 2026-10-08).", "endpoints": [] }, "toolCount": 14, "popularity": { "githubStars": 0, "npmWeekly": 9, "pypiWeekly": 19, "asOf": "2026-10-08" }, "docsUrl": "https://docs.numeral.com", "llmsTxt": "https://docs.numeral.com/llms.txt", "openapi": "https://docs.numeral.com/api-reference/v2026-03-01/openapi.json", "capabilities": [ "tax.calculate", "tax.transactions", "tax.exemptions", "tax.filing" ], "tags": [ "hosted", "paid", "closed-source", "api-key", "mcp", "openapi", "llms-txt", "sandbox", "sales-led", "go", "python", "typescript" ], "lastRelease": "2026-09-15", "graded": true, "anchor": { "graded": true, "score": 49.3, "grade": "D", "agentReady": false, "rank": 611, "ranked": true, "rankOf": 722, "categoryRank": 10, "methodology": "0.4", "run": "2026-10-01", "scores": { "ergonomics": 71, "maintenance": 60, "payments": 10, "reliability": 25, "schema": 87, "security": 47, "transparency": 45 }, "pending": [ "performance", "tasks" ], "assessment": { "confidence": "medium", "date": "2026-10-08" }, "negative": 0, "verdict": "Docs are written for agents, with a public OpenAPI spec for 32 operations, Markdown pages, llms.txt and a remote MCP server whose 14 tools are read-only by default. No status page, numeric rate limit or SLA was found, the API ignores idempotency keys, and API access is sold on a custom plan after a demo.", "bestFor": "An agent working for a seller or platform that has a Numeral account and needs tax at checkout, committed transactions for filing, and read access to nexus, registrations and filings through MCP.", "strengths": [ "Public OpenAPI 3.0.1 spec for version 2026-03-01 with 32 operations, 74 schemas and 57 enums, plus llms.txt and a Markdown copy of every docs page", "Remote MCP server at `https://mcp.numeralhq.com/mcp` documents 14 read-only tools. Four write tools are off by default and absent from `tools/list` until enabled", "Date-versioned API selected with the `X-API-Version` header, with a changelog and migration notes for each of four versions", "Errors are flat JSON with `code`, `type` and `message`, and the docs list every `type`. MCP tool errors carry a stable `error_code`", "`sk_test_` keys read and write sandbox data only, and the docs say revoking a key takes effect immediately" ], "weaknesses": [ "No status page, uptime SLA or numeric rate limit was found. The product page says rate limits can be removed on request", "The API ignores an `Idempotency-Key` header. A retried commit is safe only if the client handles `REFERENCE_ORDER_ID_ALREADY_EXISTS`", "Secret keys carry no scopes, and the MCP server has no OAuth flow. One key reads all of the account's tax data", "API access is listed under the Enterprise plan at a custom price, and the product page says to book a demo first", "SDKs are early. Go is v0.1.0, `numeral-tax` on PyPI is 0.1.0a1 from December 2025 and on npm is 0.1.0-alpha.2" ], "agentNotes": [ "Send `X-API-Version: 2026-03-01` on every call to `https://api.numeralhq.com`. Merchant, platform and certificate endpoints reject requests without it", "Commit with a stable `reference_order_id`. On `REFERENCE_ORDER_ID_ALREADY_EXISTS` look up the existing transaction, because `Idempotency-Key` is ignored", "Commit before the calculation's `expires_at`. If it has expired, calculate again and commit the new `calculation_id` with the original `reference_order_id`", "Send `amount` as the line total in minor units to `/tax/calculations` and as the per-unit price to `/tax/platform/calculations`", "Start with an `sk_test_` key. Certificate endpoints and MCP certificate tools are live only and answer `TESTMODE_NOT_SUPPORTED` or `live_mode_required`" ], "metrics": { "kind": "remote", "measured": false }, "reviewCount": 0, "avgRating": 0, "history": [ { "basis": "public evidence", "confidence": "medium", "grade": "D", "methodology": "0.4", "pending": [ "performance", "tasks" ], "run": "2026-10-01", "runLabel": "October 2026 research run", "score": 49.3 } ], "editorialScores": { "ergonomics": 71, "maintenance": 60, "payments": 10, "reliability": 25, "schema": 87, "security": 47, "transparency": 36 }, "provenanceScore": 53 }, "connect": { "install": "go get -u 'github.com/NumeralHQ/numeral-tax-go@v0.1.0'", "http": "curl --request POST \\\n --url https://api.numeralhq.com/tax/calculations \\\n --header 'Authorization: Bearer \u003ctoken\u003e' \\\n --header 'Content-Type: application/json' \\\n --header 'X-API-Version: 2026-03-01' \\\n --data '{ ... }'", "claudeCode": "claude mcp add --transport http numeral https://mcp.numeralhq.com/mcp \\\n --header \"Authorization: Bearer sk_test_...\"", "config": { "mcpServers": { "numeral": { "headers": { "Authorization": "Bearer sk_test_..." }, "type": "http", "url": "https://mcp.numeralhq.com/mcp" } } } }, "letme": { "capability": "https://letme.dev/tax.calculate", "tool": "https://letme.dev/numeral" }, "area": "domain-data", "unitPrices": [ { "item": "Filed return, Professional", "unit": "tx", "usd": 75, "note": "Per return filed. API access is listed under Enterprise at a custom price" }, { "item": "State registration, Professional", "unit": "tx", "usd": 150, "note": "One-time fee per state" } ], "provenance": { "legalEntity": "Numeral Two, Inc.", "domain": "numeral.com", "domainRegistered": "1997-10-02", "endpointOnVendorDomain": false, "terms": "https://www.numeral.com/legal/terms-of-service", "privacy": "", "statusPage": "", "changelog": "https://docs.numeral.com/api-reference/v2026-03-01/changelog", "securityTxt": "none", "checked": "2026-10-08", "notes": [ "The terms of service (last updated 10 June 2025) name Numeral Two, Inc. d/b/a Numeral, 527 Howard St, San Francisco, and are governed by California law.", "The API answers at api.numeralhq.com and the MCP server at mcp.numeralhq.com, a second domain. Numeral's docs name both hosts, and the dashboard is at dashboard.numeralhq.com.", "The privacy policy at numeral.com/legal/privacy-policy (effective 11 May 2026) covers the websites and says it does not apply to data processed through the platform and APIs. The privacy link here is the Data Processing Agreement (last updated 2 January 2024), which governs that data.", "www.numeral.com/.well-known/security.txt returns 404, as do the same paths on www.numeralhq.com and api.numeralhq.com.", "No status page was found on the site, the docs or the help centre.", "The trust centre at security.numeral.com is a Oneleet page drawn by script, which we couldn't read.", "RDAP gives registration dates of 1997-10-02 for numeral.com and 2022-07-14 for numeralhq.com." ], "score": 53 }, "pageJsonUrl": "https://www.anchorterminal.com/tools/numeral.json", "live": { "slug": "numeral", "probe": { "target": "https://api.numeralhq.com", "method": "get", "lastAt": "2026-10-08T21:12:16.935226704Z", "lastOk": true, "lastStatus": 200, "lastMs": 602, "authRequired": false, "uptime24h": 100, "uptime30d": 100, "p50ms24h": 606, "p95ms24h": 672, "samples24h": 21, "samples30d": 21, "days": [ { "date": "2026-10-08", "probes": 21, "ok": 21 } ] }, "updatedAt": "2026-10-08T21:12:16.935226704Z" } }, "facts": [ { "a": "HTTP API", "b": "HTTP API", "name": "Kind" }, { "a": "Fonoa Technologies Limited", "b": "Numeral Two, Inc.", "name": "Vendor" }, { "a": "https://api.fonoa.com", "b": "https://api.numeralhq.com", "name": "Hosted endpoint" }, { "a": "HTTP", "b": "HTTP, Streamable HTTP", "name": "Transports" }, { "a": "API key", "b": "API key", "name": "Auth" }, { "a": "Paid", "b": "Paid", "name": "Pricing" }, { "a": "no", "b": "no", "name": "x402" }, { "a": "Proprietary service. The API contract is not published. The public Terms of Service took effect on 14 May 2020 and name older seller sites", "b": "Proprietary service under Numeral's terms of service. The Go, Python and Node SDKs are Apache-2.0", "name": "Licence" }, { "a": "none", "b": "14", "name": "Tools exposed" }, { "a": "no", "b": "yes", "name": "Read-only variant documented" }, { "a": "yes", "b": "yes", "name": "llms.txt" }, { "a": "2026-10-02", "b": "2026-09-15", "name": "Last release" }, { "a": "no document linked", "b": "no date given", "name": "Terms last updated" }, { "a": "no date given", "b": "no document linked", "name": "Privacy policy last updated" }, { "a": "", "b": "not found in the text", "name": "Customer content may train models" }, { "a": "", "b": "not found in the text", "name": "Terms restrict automated access" }, { "a": "", "b": "not found in the text", "name": "Terms restrict benchmarking" }, { "a": "", "b": "not found in the text", "name": "Terms or service can change without notice" }, { "a": "", "b": "yes", "name": "Arbitration or class-action waiver" }, { "a": "none", "b": "0 stars, 9 npm/wk, 19 PyPI/wk", "name": "Popularity" } ], "faq": [ { "answer": "Fonoa scores 51.7 (D) on agent readiness against Numeral's 49.3 (D), and leads in 2 of 7 scored categories. Numeral leads on schema \u0026 documentation, agent ergonomics, payments \u0026 pricing and maintenance \u0026 community.", "question": "Which is better for AI agents, Fonoa or Numeral?" }, { "answer": "Both need an API key.", "question": "Do Fonoa and Numeral need an API key?" }, { "answer": "Yes. Fonoa has a hosted endpoint at https://api.fonoa.com and Numeral at https://api.numeralhq.com.", "question": "Can an agent call Fonoa and Numeral without installing anything?" } ], "goodFor": [ { "aheadOn": [ "Reliability, 66 against 25" ], "also": null, "goodFor": "An agent working for a company that already has a Fonoa contract and needs tax ID validation, VAT or GST calculation, or e-invoice reporting across many countries through one API.", "slug": "fonoa", "watchFor": "No self-serve signup. Sandbox, demo and production keys are issued by Fonoa after contact by email or the sales form" }, { "aheadOn": [ "Schema \u0026 documentation, 87 against 68", "Agent ergonomics, 71 against 64", "Payments \u0026 pricing, 10 against 3", "Maintenance \u0026 community, 60 against 49" ], "also": null, "goodFor": "An agent working for a seller or platform that has a Numeral account and needs tax at checkout, committed transactions for filing, and read access to nexus, registrations and filings through MCP.", "slug": "numeral", "watchFor": "No status page, uptime SLA or numeric rate limit was found. The product page says rate limits can be removed on request" } ], "job": { "capability": "tax.calculate", "name": "Tax calculate" }, "others": [ { "json": "https://www.anchorterminal.com/compare/anrok-vs-fonoa.json", "title": "Anrok vs Fonoa", "url": "https://www.anchorterminal.com/compare/anrok-vs-fonoa" }, { "json": "https://www.anchorterminal.com/compare/anrok-vs-numeral.json", "title": "Anrok vs Numeral", "url": "https://www.anchorterminal.com/compare/anrok-vs-numeral" }, { "json": "https://www.anchorterminal.com/compare/avalara-vs-fonoa.json", "title": "Avalara AvaTax vs Fonoa", "url": "https://www.anchorterminal.com/compare/avalara-vs-fonoa" }, { "json": "https://www.anchorterminal.com/compare/avalara-vs-numeral.json", "title": "Avalara AvaTax vs Numeral", "url": "https://www.anchorterminal.com/compare/avalara-vs-numeral" }, { "json": "https://www.anchorterminal.com/compare/fonoa-vs-kintsugi.json", "title": "Fonoa vs Kintsugi", "url": "https://www.anchorterminal.com/compare/fonoa-vs-kintsugi" }, { "json": "https://www.anchorterminal.com/compare/fonoa-vs-quaderno.json", "title": "Fonoa vs Quaderno", "url": "https://www.anchorterminal.com/compare/fonoa-vs-quaderno" }, { "json": "https://www.anchorterminal.com/compare/fonoa-vs-taxcloud.json", "title": "Fonoa vs TaxCloud", "url": "https://www.anchorterminal.com/compare/fonoa-vs-taxcloud" }, { "json": "https://www.anchorterminal.com/compare/fonoa-vs-taxjar.json", "title": "Fonoa vs TaxJar", "url": "https://www.anchorterminal.com/compare/fonoa-vs-taxjar" }, { "json": "https://www.anchorterminal.com/compare/fonoa-vs-vertex-tax.json", "title": "Fonoa vs Vertex O Series", "url": "https://www.anchorterminal.com/compare/fonoa-vs-vertex-tax" }, { "json": "https://www.anchorterminal.com/compare/fonoa-vs-zamp.json", "title": "Fonoa vs Zamp", "url": "https://www.anchorterminal.com/compare/fonoa-vs-zamp" }, { "json": "https://www.anchorterminal.com/compare/kintsugi-vs-numeral.json", "title": "Kintsugi vs Numeral", "url": "https://www.anchorterminal.com/compare/kintsugi-vs-numeral" }, { "json": "https://www.anchorterminal.com/compare/numeral-vs-quaderno.json", "title": "Numeral vs Quaderno", "url": "https://www.anchorterminal.com/compare/numeral-vs-quaderno" }, { "json": "https://www.anchorterminal.com/compare/numeral-vs-taxcloud.json", "title": "Numeral vs TaxCloud", "url": "https://www.anchorterminal.com/compare/numeral-vs-taxcloud" }, { "json": "https://www.anchorterminal.com/compare/numeral-vs-taxjar.json", "title": "Numeral vs TaxJar", "url": "https://www.anchorterminal.com/compare/numeral-vs-taxjar" }, { "json": "https://www.anchorterminal.com/compare/numeral-vs-vertex-tax.json", "title": "Numeral vs Vertex O Series", "url": "https://www.anchorterminal.com/compare/numeral-vs-vertex-tax" }, { "json": "https://www.anchorterminal.com/compare/numeral-vs-zamp.json", "title": "Numeral vs Zamp", "url": "https://www.anchorterminal.com/compare/numeral-vs-zamp" } ], "scores": [ { "by": 41, "edge": "fonoa", "fonoa": 66, "key": "reliability", "name": "Reliability", "numeral": 25, "weight": 16 }, { "key": "performance", "name": "Performance", "pending": true, "weight": 10 }, { "by": 19, "edge": "numeral", "fonoa": 68, "key": "schema", "name": "Schema \u0026 documentation", "numeral": 87, "weight": 13 }, { "by": 7, "edge": "numeral", "fonoa": 64, "key": "ergonomics", "name": "Agent ergonomics", "numeral": 71, "weight": 13 }, { "by": 0, "edge": "", "fonoa": 47, "key": "security", "name": "Security \u0026 auth", "numeral": 47, "weight": 14 }, { "by": 7, "edge": "numeral", "fonoa": 3, "key": "payments", "name": "Payments \u0026 pricing", "numeral": 10, "weight": 10 }, { "key": "tasks", "name": "Task success", "pending": true, "weight": 10 }, { "by": 11, "edge": "numeral", "fonoa": 49, "key": "maintenance", "name": "Maintenance \u0026 community", "numeral": 60, "weight": 7 }, { "by": 3, "edge": "fonoa", "fonoa": 48, "key": "transparency", "name": "Transparency \u0026 trust", "numeral": 45, "weight": 7 } ], "summary": "Fonoa scores 51.7 (D) on agent readiness against Numeral's 49.3 (D), and leads in 2 of 7 scored categories. Numeral leads on schema \u0026 documentation, agent ergonomics, payments \u0026 pricing and maintenance \u0026 community. Both do tax calculate.", "verdicts": { "fonoa": "The API reference is served as Markdown with an OpenAPI definition on each endpoint page, and e-invoicing submissions are idempotent by `transaction_id`. API keys are issued by Fonoa staff after contact, no price, rate limit or changelog is published, and the only public terms date from May 2020 and cover older seller sites.", "numeral": "Docs are written for agents, with a public OpenAPI spec for 32 operations, Markdown pages, llms.txt and a remote MCP server whose 14 tools are read-only by default. No status page, numeric rate limit or SLA was found, the API ignores idempotency keys, and API access is sold on a custom plan after a demo." } }, "kind": "anchor.page", "links": { "api": "https://www.anchorterminal.com/api/v1/index.json", "html": "https://www.anchorterminal.com/compare/fonoa-vs-numeral", "json": "https://www.anchorterminal.com/compare/fonoa-vs-numeral.json", "llms": "https://www.anchorterminal.com/llms.txt", "markdown": "https://www.anchorterminal.com/compare/fonoa-vs-numeral.md", "slim": "https://www.anchorterminal.com/compare/fonoa-vs-numeral.min.md" }, "markdown": "Fonoa scores 51.7 (D) on agent readiness against Numeral's 49.3 (D), and leads in 2 of 7 scored categories. Numeral leads on schema \u0026 documentation, agent ergonomics, payments \u0026 pricing and maintenance \u0026 community. Both do tax calculate.\n\n- Fonoa: grade D, 51.7/100, rank #575 of 722. Markdown https://www.anchorterminal.com/tools/fonoa.md · JSON https://www.anchorterminal.com/api/v1/tools/fonoa.json\n- Numeral: grade D, 49.3/100, rank #611 of 722. Markdown https://www.anchorterminal.com/tools/numeral.md · JSON https://www.anchorterminal.com/api/v1/tools/numeral.json\n\n## Which one, for what\n\n### Fonoa (D)\n\nGood for: An agent working for a company that already has a Fonoa contract and needs tax ID validation, VAT or GST calculation, or e-invoice reporting across many countries through one API.\n\nAhead on:\n- Reliability, 66 against 25\n\nWatch for: No self-serve signup. Sandbox, demo and production keys are issued by Fonoa after contact by email or the sales form\n\n### Numeral (D)\n\nGood for: An agent working for a seller or platform that has a Numeral account and needs tax at checkout, committed transactions for filing, and read access to nexus, registrations and filings through MCP.\n\nAhead on:\n- Schema \u0026 documentation, 87 against 68\n- Agent ergonomics, 71 against 64\n- Payments \u0026 pricing, 10 against 3\n- Maintenance \u0026 community, 60 against 49\n\nWatch for: No status page, uptime SLA or numeric rate limit was found. The product page says rate limits can be removed on request\n\n\n## Score by category\n\n| Category | Weight | Fonoa | Numeral | Edge |\n| --- | --- | --- | --- | --- |\n| Reliability | 16% (20 this run) | 66 | 25 | Fonoa +41 |\n| Performance | 10%, pending | pending | pending | not scored in this run |\n| Schema \u0026 documentation | 13% (16.2 this run) | 68 | 87 | Numeral +19 |\n| Agent ergonomics | 13% (16.2 this run) | 64 | 71 | Numeral +7 |\n| Security \u0026 auth | 14% (17.5 this run) | 47 | 47 | even |\n| Payments \u0026 pricing | 10% (12.5 this run) | 3 | 10 | Numeral +7 |\n| Task success | 10%, pending | pending | pending | not scored in this run |\n| Maintenance \u0026 community | 7% (8.8 this run) | 49 | 60 | Numeral +11 |\n| Transparency \u0026 trust | 7% (8.8 this run) | 48 | 45 | Fonoa +3 |\n| Negative events | ≤15 | 0 | 0 | |\n| **Total** | | **51.7 · D** | **49.3 · D** | |\n\n## Facts side by side\n\n| Fact | Fonoa | Numeral |\n| --- | --- | --- |\n| Kind | HTTP API | HTTP API |\n| Vendor | Fonoa Technologies Limited | Numeral Two, Inc. |\n| Hosted endpoint | `https://api.fonoa.com` | `https://api.numeralhq.com` |\n| Transports | HTTP | HTTP, Streamable HTTP |\n| Auth | API key | API key |\n| Pricing | Paid | Paid |\n| x402 | no | no |\n| Licence | Proprietary service. The API contract is not published. The public Terms of Service took effect on 14 May 2020 and name older seller sites | Proprietary service under Numeral's terms of service. The Go, Python and Node SDKs are Apache-2.0 |\n| Tools exposed | none | 14 |\n| Read-only variant documented | no | yes |\n| llms.txt | yes | yes |\n| Last release | 2026-10-02 | 2026-09-15 |\n| Terms last updated | no document linked | no date given |\n| Privacy policy last updated | no date given | no document linked |\n| Customer content may train models | | not found in the text |\n| Terms restrict automated access | | not found in the text |\n| Terms restrict benchmarking | | not found in the text |\n| Terms or service can change without notice | | not found in the text |\n| Arbitration or class-action waiver | | yes |\n| Popularity | none | 0 stars, 9 npm/wk, 19 PyPI/wk |\n\n## Verdicts\n\n**Fonoa.** The API reference is served as Markdown with an OpenAPI definition on each endpoint page, and e-invoicing submissions are idempotent by `transaction_id`. API keys are issued by Fonoa staff after contact, no price, rate limit or changelog is published, and the only public terms date from May 2020 and cover older seller sites.\n\n**Numeral.** Docs are written for agents, with a public OpenAPI spec for 32 operations, Markdown pages, llms.txt and a remote MCP server whose 14 tools are read-only by default. No status page, numeric rate limit or SLA was found, the API ignores idempotency keys, and API access is sold on a custom plan after a demo.\n\n## Before you call either\n\n### Fonoa\n\n1. Send the key in the `Ocp-Apim-Subscription-Key` header. Use the sandbox key at https://sandbox.fonoa.com and the production key at https://api.fonoa.com\n2. Treat validations and e-invoicing submissions as asynchronous. POST, then poll the GET endpoint or wait for the webhook, and avoid tight polling\n3. Reuse the same `transaction_id` on a retry of `/v1/transactions`. A transaction already processed is not processed again\n4. Commit a calculation with POST `/tax/v2/calculations/\u003cuuid\u003e/commit` only when the sale is final. The commit adds it to revenue tracking\n5. Ask the Fonoa contact to configure webhooks. There is no API for it, and always fetch `resource_url` as given in the webhook\n\n### Numeral\n\n1. Send `X-API-Version: 2026-03-01` on every call to `https://api.numeralhq.com`. Merchant, platform and certificate endpoints reject requests without it\n2. Commit with a stable `reference_order_id`. On `REFERENCE_ORDER_ID_ALREADY_EXISTS` look up the existing transaction, because `Idempotency-Key` is ignored\n3. Commit before the calculation's `expires_at`. If it has expired, calculate again and commit the new `calculation_id` with the original `reference_order_id`\n4. Send `amount` as the line total in minor units to `/tax/calculations` and as the per-unit price to `/tax/platform/calculations`\n5. Start with an `sk_test_` key. Certificate endpoints and MCP certificate tools are live only and answer `TESTMODE_NOT_SUPPORTED` or `live_mode_required`\n\n## Questions\n\n### Which is better for AI agents, Fonoa or Numeral?\n\nFonoa scores 51.7 (D) on agent readiness against Numeral's 49.3 (D), and leads in 2 of 7 scored categories. Numeral leads on schema \u0026 documentation, agent ergonomics, payments \u0026 pricing and maintenance \u0026 community.\n\n### Do Fonoa and Numeral need an API key?\n\nBoth need an API key.\n\n### Can an agent call Fonoa and Numeral without installing anything?\n\nYes. Fonoa has a hosted endpoint at https://api.fonoa.com and Numeral at https://api.numeralhq.com.\n\n\n## For agents\n\n- This comparison as JSON: https://www.anchorterminal.com/compare/fonoa-vs-numeral.json, and with the fewest tokens: https://www.anchorterminal.com/compare/fonoa-vs-numeral.min.md\n- Over MCP at https://www.anchorterminal.com/mcp (no key): `compare_tools {\"a\": \"fonoa\", \"b\": \"numeral\"}`. From a terminal: `anchor compare fonoa numeral`\n- Each listing in full: https://www.anchorterminal.com/api/v1/tools/fonoa.json and https://www.anchorterminal.com/api/v1/tools/numeral.json\n\n## Other comparisons with Fonoa or Numeral\n\n- [Anrok vs Fonoa](https://www.anchorterminal.com/compare/anrok-vs-fonoa.md)\n- [Anrok vs Numeral](https://www.anchorterminal.com/compare/anrok-vs-numeral.md)\n- [Avalara AvaTax vs Fonoa](https://www.anchorterminal.com/compare/avalara-vs-fonoa.md)\n- [Avalara AvaTax vs Numeral](https://www.anchorterminal.com/compare/avalara-vs-numeral.md)\n- [Fonoa vs Kintsugi](https://www.anchorterminal.com/compare/fonoa-vs-kintsugi.md)\n- [Fonoa vs Quaderno](https://www.anchorterminal.com/compare/fonoa-vs-quaderno.md)\n- [Fonoa vs TaxCloud](https://www.anchorterminal.com/compare/fonoa-vs-taxcloud.md)\n- [Fonoa vs TaxJar](https://www.anchorterminal.com/compare/fonoa-vs-taxjar.md)\n- [Fonoa vs Vertex O Series](https://www.anchorterminal.com/compare/fonoa-vs-vertex-tax.md)\n- [Fonoa vs Zamp](https://www.anchorterminal.com/compare/fonoa-vs-zamp.md)\n- [Kintsugi vs Numeral](https://www.anchorterminal.com/compare/kintsugi-vs-numeral.md)\n- [Numeral vs Quaderno](https://www.anchorterminal.com/compare/numeral-vs-quaderno.md)\n- [Numeral vs TaxCloud](https://www.anchorterminal.com/compare/numeral-vs-taxcloud.md)\n- [Numeral vs TaxJar](https://www.anchorterminal.com/compare/numeral-vs-taxjar.md)\n- [Numeral vs Vertex O Series](https://www.anchorterminal.com/compare/numeral-vs-vertex-tax.md)\n- [Numeral vs Zamp](https://www.anchorterminal.com/compare/numeral-vs-zamp.md)\n", "meta": { "attribution": "Anchor Terminal (https://www.anchorterminal.com)", "docs": "https://www.anchorterminal.com/docs/", "generatedAt": "2026-10-08", "license": "CC-BY-4.0", "method": "https://www.anchorterminal.com/benchmark/", "methodology": "0.4", "openapi": "https://www.anchorterminal.com/openapi.json", "preview": false, "run": "2026-10-01", "runLabel": "October 2026 research run" }, "page": { "breadcrumbs": [ { "name": "Home", "url": "https://www.anchorterminal.com/" }, { "name": "Compare", "url": "https://www.anchorterminal.com/compare/" }, { "name": "Fonoa vs Numeral", "url": "" } ], "description": "Fonoa scores 51.7 (D) on agent readiness against Numeral's 49.3 (D), and leads in 2 of 7 scored categories. Numeral leads on schema \u0026 documentation, agent ergonomics, payments \u0026 pricing and maintenance \u0026 community. Both do tax calculate. Category scores, facts, verdicts and…", "facts": [ "Fonoa D 51.7", "Numeral D 49.3", "scores" ], "h1": "Fonoa vs Numeral", "image": "https://www.anchorterminal.com/assets/og/compare-fonoa-vs-numeral.png", "path": "/compare/fonoa-vs-numeral", "published": "2026-10-01", "section": "tools", "title": "Fonoa vs Numeral for AI agents, D 51.7 vs D 49.3 | Anchor Terminal", "toc": null, "updated": "2026-10-08", "url": "https://www.anchorterminal.com/compare/fonoa-vs-numeral" }, "tokens": { "markdown": 2200, "slim": 730 }, "version": 1 }