# calcular_margem_contribuicao

Calcula a Margem de Contribuição (MC) e uma DRE (Demonstração de Resultado) simplificada. Margem de Contribuição = Receita Líquida − Custos Variáveis. MC% = MC / Receita Líquida × 100 — percentual que cada R$1 de receita contribui para cobrir custos fixos. Quando custosFixos informado: Resultado Operacional = MC − Custos Fixos; Ponto de Equilíbrio = Custos Fixos / MC%; Folga = receita atual − PE. Custos variáveis podem ser informados como total agregado OU como array categorizado (custosVariaveisDetalhados).

Agent View of the PolicyLayer registry record for `calcular_margem_contribuicao`. HTML page: https://policylayer.com/tools/io-github-lfhillesheim-contai-mcp-server/calcular-margem-contribuicao

## Facts

- Tool: `calcular_margem_contribuicao`
- Server: Contaí — Calculadoras Fiscais Brasileiras (`@contai-evoluke/mcp-server`) — https://policylayer.com/tools/io-github-lfhillesheim-contai-mcp-server.md
- Install: `npx -y @contai-evoluke/mcp-server`
- Homepage: https://github.com/lfhillesheim/calculadora
- Risk category: Read (Low risk)
- Registry record: grade B, identity unverified
- Server rate-limited: no
- Parameters: 5 (2 required)
- Recommended policy verdict: Allowed

## Parameters

| Parameter | Type | Required | Description |
| --- | --- | --- | --- |
| `deducoesCents` | integer | no | Total de deduções da receita bruta em centavos (impostos sobre faturamento, devoluções, descontos). Receita Líquida = Receita Bruta − Deduções. Default: 0. Ex: |
| `custosFixosCents` | integer | no | Total de custos fixos do período em centavos (aluguel, salários, contador). Quando informado, calcula o resultado operacional e o ponto de equilíbrio. Default: |
| `receitaBrutaCents` | integer | yes | Receita bruta total do período em centavos (faturamento antes de deduções). Ex: R$ 50.000 → 5000000 |
| `custosVariaveisCents` | integer | yes | Total agregado de custos variáveis em centavos (matéria-prima, comissão de vendas, frete). Ignorado quando "custosVariaveisDetalhados" tem itens. Devem ser meno |
| `custosVariaveisDetalhados` | array | no | Custos variáveis detalhados por categoria (materia_prima, frete_logistica, marketing, mao_de_obra, software_assinaturas, outro). Cada item: { categoria, valorCe |

Parameters from the server's own tool schema.

## Example call (MCP tools/call, JSON-RPC 2.0)

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "calcular_margem_contribuicao",
    "arguments": {
      "receitaBrutaCents": 0,
      "custosVariaveisCents": 0
    }
  }
}
```

## Why calcular_margem_contribuicao is rated Low

This tool retrieves or computes derived financial metrics from provided inputs (revenue, variable costs, fixed costs) without modifying, creating, deleting, or persisting data. It is purely computational and analytical—similar to a calculator or query that returns read-only analysis. No side effects, reversible operations, or irreversible actions are performed.

From the tool's own definition: "Tool performs financial calculations and analysis: 'Calcula a Margem de Contribuição (MC) e uma DRE (Demonstração de Resultado) simplificada' with formulas like 'MC = Receita Líquida − Custos Variáveis' and 'MC% = MC / Receita Líquida × 100'."

## Use case

AI agents call calcular_margem_contribuicao to retrieve information from Contaí — Calculadoras Fiscais Brasileiras without modifying anything. It is typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.

## Recommended policy (PolicyLayer)

Verdict: **Allowed**. Enforced by the PolicyLayer MCP gateway (https://policylayer.com/mcp-gateway) before a call reaches Contaí — Calculadoras Fiscais Brasileiras:

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "calcular_margem_contribuicao": {}
  }
}
```

## Other tools on Contaí — Calculadoras Fiscais Brasileiras (138)

- `calcular_mensalidade_planejador` — Financial — https://policylayer.com/tools/io-github-lfhillesheim-contai-mcp-server/calcular-mensalidade-planejador.md
- `buscar_lei` — Read — https://policylayer.com/tools/io-github-lfhillesheim-contai-mcp-server/buscar-lei.md
- `calcular_13o_salario` — Read — https://policylayer.com/tools/io-github-lfhillesheim-contai-mcp-server/calcular-13o-salario.md
- `calcular_acao_trabalhista` — Read — https://policylayer.com/tools/io-github-lfhillesheim-contai-mcp-server/calcular-acao-trabalhista.md
- `calcular_adicional_noturno` — Read — https://policylayer.com/tools/io-github-lfhillesheim-contai-mcp-server/calcular-adicional-noturno.md
- `calcular_alocador_50_30_20` — Read — https://policylayer.com/tools/io-github-lfhillesheim-contai-mcp-server/calcular-alocador-50-30-20.md
- `calcular_aluguel_reajuste` — Read — https://policylayer.com/tools/io-github-lfhillesheim-contai-mcp-server/calcular-aluguel-reajuste.md
- `calcular_aluguel_vs_compra_imovel` — Read — https://policylayer.com/tools/io-github-lfhillesheim-contai-mcp-server/calcular-aluguel-vs-compra-imovel.md
- `calcular_auditoria_beneficios_trabalhistas` — Read — https://policylayer.com/tools/io-github-lfhillesheim-contai-mcp-server/calcular-auditoria-beneficios-trabalhistas.md
- `calcular_auxilio_doenca` — Read — https://policylayer.com/tools/io-github-lfhillesheim-contai-mcp-server/calcular-auxilio-doenca.md
- `calcular_aviso_previo` — Read — https://policylayer.com/tools/io-github-lfhillesheim-contai-mcp-server/calcular-aviso-previo.md
- `calcular_banco_de_horas` — Read — https://policylayer.com/tools/io-github-lfhillesheim-contai-mcp-server/calcular-banco-de-horas.md
- `calcular_bdr_vs_etf_vs_acao_direta` — Read — https://policylayer.com/tools/io-github-lfhillesheim-contai-mcp-server/calcular-bdr-vs-etf-vs-acao-direta.md
- `calcular_bola_de_neve_dividas` — Read — https://policylayer.com/tools/io-github-lfhillesheim-contai-mcp-server/calcular-bola-de-neve-dividas.md
- `calcular_bolsa_estagio` — Read — https://policylayer.com/tools/io-github-lfhillesheim-contai-mcp-server/calcular-bolsa-estagio.md
- `calcular_calculadora_gestacional` — Read — https://policylayer.com/tools/io-github-lfhillesheim-contai-mcp-server/calcular-calculadora-gestacional.md
- `calcular_calculadora_milhas_passagem` — Read — https://policylayer.com/tools/io-github-lfhillesheim-contai-mcp-server/calcular-calculadora-milhas-passagem.md
- `calcular_calorias_macros` — Read — https://policylayer.com/tools/io-github-lfhillesheim-contai-mcp-server/calcular-calorias-macros.md
- `calcular_capital_de_giro_necessario` — Read — https://policylayer.com/tools/io-github-lfhillesheim-contai-mcp-server/calcular-capital-de-giro-necessario.md
- `calcular_carne_leao` — Read — https://policylayer.com/tools/io-github-lfhillesheim-contai-mcp-server/calcular-carne-leao.md
- `calcular_cartao_credito_cashback_anuidade` — Read — https://policylayer.com/tools/io-github-lfhillesheim-contai-mcp-server/calcular-cartao-credito-cashback-anuidade.md
- `calcular_cdb_vs_lci_vs_tesouro_vs_poupanca` — Read — https://policylayer.com/tools/io-github-lfhillesheim-contai-mcp-server/calcular-cdb-vs-lci-vs-tesouro-vs-poupanca.md
- `calcular_comparador_regime_tributario` — Read — https://policylayer.com/tools/io-github-lfhillesheim-contai-mcp-server/calcular-comparador-regime-tributario.md
- `calcular_consorcio_credito_empresarial` — Read — https://policylayer.com/tools/io-github-lfhillesheim-contai-mcp-server/calcular-consorcio-credito-empresarial.md
- `calcular_consorcio_vs_financiamento` — Read — https://policylayer.com/tools/io-github-lfhillesheim-contai-mcp-server/calcular-consorcio-vs-financiamento.md
- `calcular_consultoria_pj_saude_financeira` — Read — https://policylayer.com/tools/io-github-lfhillesheim-contai-mcp-server/calcular-consultoria-pj-saude-financeira.md
- `calcular_consumo_agua` — Read — https://policylayer.com/tools/io-github-lfhillesheim-contai-mcp-server/calcular-consumo-agua.md
- `calcular_conversao_moedas_iof` — Read — https://policylayer.com/tools/io-github-lfhillesheim-contai-mcp-server/calcular-conversao-moedas-iof.md
- `calcular_credito_pj_comparador` — Read — https://policylayer.com/tools/io-github-lfhillesheim-contai-mcp-server/calcular-credito-pj-comparador.md
- `calcular_custo_efetivo_total` — Read — https://policylayer.com/tools/io-github-lfhillesheim-contai-mcp-server/calcular-custo-efetivo-total.md
- …and 108 more: https://policylayer.com/tools/io-github-lfhillesheim-contai-mcp-server.md

## For agents

This record is a snapshot. Live verdicts and the full registry:

- Check every server in your MCP config at once: `npx -y policylayer stack`
- Vet a server before you add it: install the mcp-precheck skill — `npx skills add https://policylayer.com` (skill text: https://policylayer.com/skill.md)
- Query the registry over MCP: endpoint `https://api.policylayer.com/mcp` — tools `check_mcp_server`, `check_mcp_stack`, `check_tool`, `search_registry`, `get_change_events`

---

Source: the PolicyLayer MCP registry — one continuously verified record per MCP server. Full record: https://policylayer.com/registry?q=io-github-lfhillesheim-contai-mcp-server · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/io-github-lfhillesheim-contai-mcp-server