# Simples Nacional Calculator MCP > Simples Nacional Calculator handles complex Brazilian tax calculations for small businesses. It automatically determines effective tax rates, checks eligibility for the Fator R reduction tier, and figures out your total monthly DAS amount based on specific revenue brackets across all five Annexes (I through V). This MCP lets your agent accurately estimate required federal taxes without manual spreadsheet work. ## Overview - **Category:** finance - **Price:** Free - **Tags:** brazil, simples-nacional, tax-calculator, das, fator-r ## Description Need to figure out a business's tax liability under Brazil’s Simples Nacional regime? This MCP provides the calculation engine for that. It takes raw financial data and calculates complex variables like effective rates and necessary deductions, which are usually handled by specialized local accounting software. It handles progressive revenue tiers across multiple Annexes (I through V), so you don't have to worry about tracking accumulated revenue or fixed deduction thresholds yourself. You can run a check to see if the business qualifies for the Fator R reduction tier by comparing payroll expenses against gross sales, giving you an accurate estimate of the monthly tax payment (DAS) due. When your agent runs these figures, it doesn't just spit out numbers; it provides structured data that tells you exactly which tax bracket applies and why. This level of precision is critical when dealing with compliance. Remember, while Vinkius hosts this MCP, we also enforce a financial circuit breaker with human-in-the-loop approval on every call that touches money. Your AI sets the intent, but no transaction fires without your explicit sign-off. ## Tools ### calculate_effective_rate Determines the precise, dynamic percentage rate that applies to the revenue. ### compute_monthly_tax_amount Calculates the total final tax amount (DAS) due for a given month's activity. ### evaluate_factor_r Checks if the company qualifies for lower taxation tiers by analyzing payroll costs versus gross revenue. ### get_bracket_parameters Retrieves necessary tax constants and specific bracket thresholds based on the activity type and revenue size. ## Prompt Examples **Prompt:** ``` Calculate the effective tax rate for a company with 200,000 BRL accumulated revenue in Annex I, using a nominal rate of 4% and deduction of 0. ``` **Response:** ``` The effective tax rate is 4.0%. ``` **Prompt:** ``` Check if a company with 100,000 BRL revenue and 30,000 BRL payroll qualifies for Fator R. ``` **Response:** ``` The company is eligible for the lower taxation tier (Annex III) because the payroll-to-revenue ratio is 30%. ``` **Prompt:** ``` How much tax will I pay this month if my revenue is 5,000 BRL and my effective rate is 6%? ``` **Response:** ``` The total tax due (DAS) for this month is 300.00 BRL. ``` ## Capabilities ### Determine Effective Tax Rates It calculates the actual percentage tax rate applied to revenue based on accumulated earnings and current deductions. ### Check Fator R Eligibility The MCP assesses if the company qualifies for reduced taxation tiers by comparing payroll spending to total gross revenue. ### Calculate Final Tax Payments It outputs a concrete, final tax amount (DAS) that must be paid for the reporting month. ## Use Cases ### A new client needs tax modeling The analyst asks the agent: 'Calculate the effective rate and projected DAS for a 10,000 BRL revenue month with these payroll details.' The MCP uses `get_bracket_parameters` first, then runs `calculate_effective_rate`, finally using `compute_monthly_tax_amount` to deliver the final tax due. ### Checking for rate reductions A business owner needs to know if they qualify for a lower tax bracket. They simply prompt: 'Check my Fator R status.' The agent runs `evaluate_factor_r` and instantly returns the eligibility status, preventing them from overpaying or underreporting. ### Comparing Annexes An accountant needs to compare tax liability across different business activities. They prompt for calculations against various revenue figures in different annexes, letting the agent cycle through rates and calculate the final DAS using `calculate_effective_rate`. ### Quick compliance check During a meeting, you need to give an instant tax estimate. You prompt for the monthly payment given revenue and payroll data. The agent orchestrates all necessary steps to provide a single, reliable figure using `compute_monthly_tax_amount`. ## Benefits - Stop relying on complex spreadsheets. The MCP handles the progressive revenue tiers across all Annexes, so you get a single, accurate rate calculation instead of dozens of manual checks. - Confirm Fator R eligibility instantly. Instead of manually comparing payroll records to gross sales, `evaluate_factor_r` tells you right away if the company qualifies for lower taxes. - Determine tax liability accurately. The system uses `get_bracket_parameters` first, ensuring that all calculations are based on the current official tax constants. - Get a final number without guessing. You don't just get rates; `compute_monthly_tax_amount` provides the definitive DAS figure required for filing. - Save hours of cross-referencing. By chaining these tools together, you move from data gathering to actionable compliance figures in minutes. ## How It Works The bottom line is that you send in raw financial inputs, and the MCP returns the precise, calculated tax liability. 1. Input your business data: Provide the accumulated revenue figures and the specific annex/tax bracket details. 2. The MCP processes the variables by first checking tax constants, then evaluating the Fator R status and calculating the dynamic effective rate. 3. You get back a final calculation detailing the total required monthly tax amount (DAS) for compliance. ## Frequently Asked Questions **How can I find the tax rate for my business activity?** You can use the `get_bracket_parameters` tool. Provide your accumulated revenue from the last 12 months and the specific Annex type (e.g., Annex I for commerce) to retrieve the nominal rate and deduction amount. **What is Fator R and how does it affect my taxes?** Fator R is a rule for certain service activities. By using `evaluate_factor_r`, you can check if your payroll costs relative to revenue allow you to move from Annex V to the more favorable Annex III. **Can I calculate the exact amount of DAS to pay?** Yes. After determining your effective rate, use `compute_monthly_tax_amount` with your current month's revenue to get the final currency value of your tax liability. **How does `calculate_effective_rate` handle accumulated revenue from multiple months?** It calculates the rate based on the Rolling 12-month Revenue (RBT12) average. You must provide the total accumulated gross revenue for the last twelve months and the specific annex code to ensure accuracy. **What inputs are needed when using `get_bracket_parameters`?** You need three things: your CNAE (activity code), the current month's gross revenue, and the applicable tax Annex. Providing all three parameters ensures the correct taxation constants are retrieved. **If I run `compute_monthly_tax_amount` with conflicting data, what happens?** The system will return a structured error message detailing which input fields conflict or are missing. This allows you to trace the exact point of failure in your tax data. **Can I use `evaluate_factor_r` if my payroll expenses were paid retroactively?** Yes, as long as you provide accurate documentation for the actual expense dates. The tool accepts historical payroll expenditure data to determine current eligibility status. **What is the proper order of operations when using `get_bracket_parameters` and then `calculate_effective_rate`?** First, use `get_bracket_parameters` to confirm your applicable tax brackets. Then, feed those confirmed constants into `calculate_effective_rate` for a precise final calculation.