{"openapi":"3.1.0","info":{"title":"HK Profits Tax Estimator API","version":"0.1.0","description":"Read-only arithmetic on the profits tax rates published by the Hong Kong Inland Revenue Department: for years of assessment 2018/19 onwards, corporations pay 8.25% on the first HK$2,000,000 of assessable profits and 16.5% above; unincorporated businesses pay 7.5% on the first HK$2,000,000 and 15% above; the standard rates (16.5% and 15%) apply to an entity that does not take the lower tier....\n\nEvery operation is read-only or compute-only. The same tools are available over MCP (streamable HTTP) at https://hk-profits-tax.connectorbay.com/mcp.\n\nDisclaimer: General information only, not legal, tax, accounting or payment advice. HK Profits Tax Estimator 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/hk-profits-tax/docs"},"termsOfService":"https://connectorbay.com/hk-profits-tax/terms"},"servers":[{"url":"https://hk-profits-tax.connectorbay.com"}],"externalDocs":{"url":"https://connectorbay.com/hk-profits-tax/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/estimate_profits_tax":{"post":{"operationId":"estimate_profits_tax","summary":"Estimate profits tax on an assessable profit under the two-tiered rates (or the standard rate) for a corporation or an u","description":"Estimate profits tax on an assessable profit under the two-tiered rates (or the standard rate) for a corporation or an unincorporated business, with the effective rate. Use for \"What is the profits tax on HK$3,000,000 of assessable profits for my company?\".","tags":["tools"],"requestBody":{"required":true,"content":{"application/json":{"schema":{"properties":{"assessable_profit":{"description":"Assessable profits in HK dollars for the year of assessment, as a decimal string (zero or more; losses are not modelled)","title":"Assessable Profit","type":"string"},"entity_type":{"description":"corporation or unincorporated (sole proprietorship, partnership or other unincorporated business)","title":"Entity Type","type":"string"},"lower_tier_elected":{"default":true,"description":"True if this entity takes the two-tiered rates; false when it does not (for example another connected entity was nominated), so the standard rate applies to all profits","title":"Lower Tier Elected","type":"boolean"},"year_of_assessment":{"anyOf":[{"type":"string"},{"type":"null"}],"default":null,"description":"Year of assessment as YYYY/YY, for example 2026/27 (1 April to 31 March); 2018/19 or later; defaults to the year containing today's date (UTC)","title":"Year Of Assessment"}},"required":["assessable_profit","entity_type"],"title":"estimate_profits_taxArguments","type":"object"}}}},"responses":{"200":{"description":"Tool result. `ok: true` on success; `ok: false` with a structured `error` (provider_unavailable, upstream_error, bad_input) when the tool could not answer.","content":{"application/json":{"schema":{"type":"object","additionalProperties":true}}}},"422":{"description":"Arguments failed validation","content":{"application/json":{"schema":{"$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/compare_entity_types":{"post":{"operationId":"compare_entity_types","summary":"Side-by-side profits tax of a company and an unincorporated business at the same assessable profit, both taking the lowe","description":"Side-by-side profits tax of a company and an unincorporated business at the same assessable profit, both taking the lower tier. Use for \"At HK$2,500,000 of profit, how does profits tax compare between a limited company and a sole proprietorship?\".","tags":["tools"],"requestBody":{"required":true,"content":{"application/json":{"schema":{"properties":{"assessable_profit":{"description":"Assessable profits in HK dollars, as a decimal string (zero or more)","title":"Assessable Profit","type":"string"},"year_of_assessment":{"anyOf":[{"type":"string"},{"type":"null"}],"default":null,"description":"Year of assessment as YYYY/YY, for example 2026/27 (1 April to 31 March); 2018/19 or later; defaults to the year containing today's date (UTC)","title":"Year Of Assessment"}},"required":["assessable_profit"],"title":"compare_entity_typesArguments","type":"object"}}}},"responses":{"200":{"description":"Tool result. `ok: true` on success; `ok: false` with a structured `error` (provider_unavailable, upstream_error, bad_input) when the tool could not answer.","content":{"application/json":{"schema":{"type":"object","additionalProperties":true}}}},"422":{"description":"Arguments failed validation","content":{"application/json":{"schema":{"$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/sensitivity_table":{"post":{"operationId":"sensitivity_table","summary":"Profits tax and effective rate at several profit levels for one entity type. Use for \"Show me profits tax for a company ","description":"Profits tax and effective rate at several profit levels for one entity type. Use for \"Show me profits tax for a company at HK$500,000, 1 million, 2 million, 3 million and 5 million of profit\".","tags":["tools"],"requestBody":{"required":true,"content":{"application/json":{"schema":{"properties":{"entity_type":{"description":"corporation or unincorporated","title":"Entity Type","type":"string"},"profit_levels":{"anyOf":[{"items":{"type":"string"},"type":"array"},{"type":"null"}],"default":null,"description":"Assessable profit levels in HK dollars as decimal strings (1 to 20 values); defaults to 500000, 1000000, 2000000, 3000000, 5000000, 10000000","title":"Profit Levels"},"lower_tier_elected":{"default":true,"description":"True if the entity takes the two-tiered rates; false for the standard rate on all profits","title":"Lower Tier Elected","type":"boolean"},"year_of_assessment":{"anyOf":[{"type":"string"},{"type":"null"}],"default":null,"description":"Year of assessment as YYYY/YY, for example 2026/27 (1 April to 31 March); 2018/19 or later; defaults to the year containing today's date (UTC)","title":"Year Of Assessment"}},"required":["entity_type"],"title":"sensitivity_tableArguments","type":"object"}}}},"responses":{"200":{"description":"Tool result. `ok: true` on success; `ok: false` with a structured `error` (provider_unavailable, upstream_error, bad_input) when the tool could not answer.","content":{"application/json":{"schema":{"type":"object","additionalProperties":true}}}},"422":{"description":"Arguments failed validation","content":{"application/json":{"schema":{"$ref":"#/components/schemas/Error"}}}},"429":{"description":"Rate limit exceeded (see Retry-After)","content":{"application/json":{"schema":{"$ref":"#/components/schemas/Error"}}}}},"x-read-only":true}},"/v1/tools/connected_entity_note":{"post":{"operationId":"connected_entity_note","summary":"The rule that only one of several connected entities may take the two-tiered rates, how connection is defined and how th","description":"The rule that only one of several connected entities may take the two-tiered rates, how connection is defined and how the election is made. Use for \"I run two companies under the same owner: can both use the 8.25% rate?\".","tags":["tools"],"requestBody":{"required":true,"content":{"application/json":{"schema":{"properties":{},"title":"connected_entity_noteArguments","type":"object"}}}},"responses":{"200":{"description":"Tool result. `ok: true` on success; `ok: false` with a structured `error` (provider_unavailable, upstream_error, bad_input) when the tool could not answer.","content":{"application/json":{"schema":{"type":"object","additionalProperties":true}}}},"422":{"description":"Arguments failed validation","content":{"application/json":{"schema":{"$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/rate_schedule":{"post":{"operationId":"rate_schedule","summary":"The standard and two-tiered profits tax rates and the HK$2,000,000 threshold for a year of assessment, with sources. Use","description":"The standard and two-tiered profits tax rates and the HK$2,000,000 threshold for a year of assessment, with sources. Use for \"What are the current Hong Kong profits tax rates?\".","tags":["tools"],"requestBody":{"required":true,"content":{"application/json":{"schema":{"properties":{"year_of_assessment":{"anyOf":[{"type":"string"},{"type":"null"}],"default":null,"description":"Year of assessment as YYYY/YY, for example 2026/27 (1 April to 31 March); 2018/19 or later; defaults to the year containing today's date (UTC)","title":"Year Of Assessment"}},"title":"rate_scheduleArguments","type":"object"}}}},"responses":{"200":{"description":"Tool result. `ok: true` on success; `ok: false` with a structured `error` (provider_unavailable, upstream_error, bad_input) when the tool could not answer.","content":{"application/json":{"schema":{"type":"object","additionalProperties":true}}}},"422":{"description":"Arguments failed validation","content":{"application/json":{"schema":{"$ref":"#/components/schemas/Error"}}}},"429":{"description":"Rate limit exceeded (see Retry-After)","content":{"application/json":{"schema":{"$ref":"#/components/schemas/Error"}}}}},"x-read-only":true}}}}