{"openapi":"3.1.0","info":{"title":"UK MTD Deadlines API","version":"0.1.0","description":"UK MTD Deadlines answers the recurring Making Tax Digital date questions for sole traders, landlords and VAT-registered businesses using GOV.UK guidance. itsa_mandation_check maps qualifying income for 2024-25, 2025-26 and 2026-27 to the April 2026, 2027 or 2028 start date. quarterly_update_dates lists the four update periods and the 7 August, 7 November, 7 February and 7 May deadlines for...\n\nEvery operation is read-only or compute-only. The same tools are available over MCP (streamable HTTP) at https://uk-mtd-deadlines.connectorbay.com/mcp.\n\nDisclaimer: General information only, not legal, tax, accounting or payment advice. UK MTD Deadlines is an independent tool: it is not affiliated with, endorsed by or operated by any government body, central bank, standards body or scheme operator. Rates, thresholds and rules change; check the cited official source and confirm with a qualified professional before you rely on a result.","contact":{"name":"Unify Dynamics LLC","email":"agent@connectorbay.com","url":"https://connectorbay.com/uk-mtd-deadlines/docs"},"termsOfService":"https://connectorbay.com/uk-mtd-deadlines/terms"},"servers":[{"url":"https://uk-mtd-deadlines.connectorbay.com"}],"externalDocs":{"url":"https://connectorbay.com/uk-mtd-deadlines/docs"},"security":[{},{"bearer":[]}],"components":{"securitySchemes":{"bearer":{"type":"http","scheme":"bearer","description":"Optional. A Pro API key raises rate limits; no credentials are required."}},"schemas":{"Error":{"type":"object","properties":{"ok":{"const":false},"error":{"type":"object"}}}}},"paths":{"/v1/tools/itsa_mandation_check":{"post":{"operationId":"itsa_mandation_check","summary":"Map qualifying income for 2024-25, 2025-26 and 2026-27 to the 6 April 2026, 2027 or 2028 Making Tax Digital for Income T","description":"Map qualifying income for 2024-25, 2025-26 and 2026-27 to the 6 April 2026, 2027 or 2028 Making Tax Digital for Income Tax start date. 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Use for \"What are the quarterly update deadlines for 2026-27?\".","tags":["tools"],"requestBody":{"required":true,"content":{"application/json":{"schema":{"properties":{"tax_year":{"description":"Tax year written 2026-27 (also 2027-28 and 2028-29)","title":"Tax Year","type":"string"},"quarter_basis":{"default":"standard","description":"standard (quarters ending 5 July, 5 October, 5 January, 5 April) or calendar (30 June, 30 September, 31 December, 31 March)","title":"Quarter Basis","type":"string"}},"required":["tax_year"],"title":"quarterly_update_datesArguments","type":"object"}}}},"responses":{"200":{"description":"Tool result. `ok: true` on success; `ok: false` with a structured `error` (provider_unavailable, upstream_error, bad_input) when the tool could not answer.","content":{"application/json":{"schema":{"type":"object","additionalProperties":true}}}},"422":{"description":"Arguments failed validation","content":{"application/json":{"schema":{"$ref":"#/components/schemas/Error"}}}},"429":{"description":"Rate limit exceeded (see Retry-After)","content":{"application/json":{"schema":{"$ref":"#/components/schemas/Error"}}}}},"x-read-only":true}},"/v1/tools/next_quarterly_deadline":{"post":{"operationId":"next_quarterly_deadline","summary":"From a date, the next quarterly update deadline and the days left. 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Use for \"When is my next Making Tax Digital quarterly update due?\".","tags":["tools"],"requestBody":{"required":true,"content":{"application/json":{"schema":{"properties":{"quarter_basis":{"default":"standard","description":"standard (quarters ending 5 July, 5 October, 5 January, 5 April) or calendar (30 June, 30 September, 31 December, 31 March)","title":"Quarter Basis","type":"string"},"on_date":{"anyOf":[{"type":"string"},{"type":"null"}],"default":null,"description":"Date to measure from, YYYY-MM-DD (default today)","title":"On Date"}},"title":"next_quarterly_deadlineArguments","type":"object"}}}},"responses":{"200":{"description":"Tool result. `ok: true` on success; `ok: false` with a structured `error` (provider_unavailable, upstream_error, bad_input) when the tool could not answer.","content":{"application/json":{"schema":{"type":"object","additionalProperties":true}}}},"422":{"description":"Arguments failed validation","content":{"application/json":{"schema":{"$ref":"#/components/schemas/Error"}}}},"429":{"description":"Rate limit exceeded (see Retry-After)","content":{"application/json":{"schema":{"$ref":"#/components/schemas/Error"}}}}},"x-read-only":true}},"/v1/tools/penalty_points_status":{"post":{"operationId":"penalty_points_status","summary":"Compare missed submission deadlines with the 4-point threshold and the GBP 200 penalty. 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