IBGE Brasil MCP

Frequência e ranking de nomes

ibge_nomes

Read-onlyIdempotent

Query Brazilian name frequency by decade or rank the most popular names, filtering results by sex and IBGE locality code.

Instructions

Queries name frequency and rankings in Brazil (IBGE).

Features:

Name frequency (tipo='frequencia'):
- Birth frequency by decade
- Multiple names separated by comma
- Filter by sex and locality
Name ranking (tipo='ranking'):
- Most popular names
- Filter by decade, sex, and locality

Available decades: 1930-2010

Examples:

Frequency of "Maria": tipo="frequencia", nomes="Maria"
Compare names: tipo="frequencia", nomes="João,José,Pedro"
2000s ranking: tipo="ranking", decada=2000
Female names: tipo="ranking", sexo="F"

Behavior: read-only and idempotent — a live GET against the public IBGE Nomes (Censo) API. Returns a Markdown table.

Input Schema

TableJSON Schema

Name	Required	Description
`sexo`	No	Filtrar por sexo: M (masculino) ou F (feminino)
`tipo`	Yes	Tipo de consulta: 'frequencia' para buscar nomes específicos ou 'ranking' para ver os mais populares
`nomes`	No	Para tipo='frequencia': Nome ou nomes separados por vírgula
`decada`	No	Para tipo='ranking': Década do ranking (ex: 1990, 2000, 2010)
`limite`	No	Para tipo='ranking': Número de nomes (padrão: 20)
`localidade`	No	Código IBGE da localidade (UF: 2 dígitos, Município: 7 dígitos)

Output Schema

TableJSON Schema

Name	Required	Description
`tipo`	Yes	Tipo da consulta realizada
`ranking`	No	Resultado do ranking (presente quando tipo='ranking')
`frequencia`	No	Resultados de frequência (presente quando tipo='frequencia')
`provenance`	Yes	Bloco de proveniência (contrato v1.0): fonte, URL, período, extração e licença
`attribution`	Yes	URLs canônicas das fontes desta resposta (lista de atribuição)

Schema Changelog

Changes observed during successful MCP inspections.

Changed1 schema field changedv5.0.0Sep 12, 2026
- addedInput schema / additionalProperties
```
Added value: +false
```
Changed8 schema fields changedv4.0.0Aug 29, 2026
- removedOutput schema / properties / frequencia / items / properties / sexo / anyOf
```
Removed value: -[
-  {
-    "type": "string"
-  },
-  {
-    "type": "null"
-  }
-]
```
- addedOutput schema / properties / frequencia / items / properties / sexo / type
```
Added value: +[
+  "string",
+  "null"
+]
```
- removedOutput schema / properties / provenance / properties / data_vintage / anyOf
```
Removed value: -[
-  {
-    "type": "string"
-  },
-  {
-    "type": "null"
-  }
-]
```
- addedOutput schema / properties / provenance / properties / data_vintage / type
```
Added value: +[
+  "string",
+  "null"
+]
```
- removedOutput schema / properties / provenance / properties / license / anyOf
```
Removed value: -[
-  {
-    "type": "string"
-  },
-  {
-    "type": "null"
-  }
-]
```
- addedOutput schema / properties / provenance / properties / license / type
```
Added value: +[
+  "string",
+  "null"
+]
```
- removedOutput schema / properties / ranking / properties / sexo / anyOf
```
Removed value: -[
-  {
-    "type": "string"
-  },
-  {
-    "type": "null"
-  }
-]
```
- addedOutput schema / properties / ranking / properties / sexo / type
```
Added value: +[
+  "string",
+  "null"
+]
```

Changed10 schema fields changedv3.3.0Aug 17, 2026

changedInput schema / $schema

Previous value: -"http://json-schema.org/draft-07/schema#"New value: +"https://json-schema.org/draft/2020-12/schema"

removedInput schema / additionalProperties
```
Removed value: -false
```

changedOutput schema / $schema

Previous value: -"http://json-schema.org/draft-07/schema#"New value: +"https://json-schema.org/draft/2020-12/schema"

addedOutput schema / properties / attribution

Added value: +{
+  "description": "URLs canônicas das fontes desta resposta (lista de atribuição)",
+  "items": {
+    "type": "string"
+  },
+  "type": "array"
+}

addedOutput schema / properties / frequencia / items / properties / sexo / anyOf

Added value: +[
+  {
+    "type": "string"
+  },
+  {
+    "type": "null"
+  }
+]

removedOutput schema / properties / frequencia / items / properties / sexo / type
```
Removed value: -[
-  "string",
-  "null"
-]
```

addedOutput schema / properties / provenance

Added value: +{
+  "additionalProperties": false,
+  "description": "Bloco de proveniência (contrato v1.0): fonte, URL, período, extração e licença",
+  "properties": {
+    "citation": {
+      "description": "Citação pronta para uso",
+      "type": "string"
+    },
+    "data_vintage": {
+      "anyOf": [
+        {
+          "type": "string"
+        },
+        {
+          "type": "null"
+        }
+      ],
+      "description": "Período de referência do dado segundo a fonte; null se a fonte não expõe"
+    },
+    "license": {
+      "anyOf": [
+        {
+          "type": "string"
+        },
+        {
+          "type": "null"
+        }
+      ],
+      "description": "Regime legal do dado"
+    },
+    "retrieved_at": {
+      "description": "Instante real da extração no upstream (ISO-8601, horário de Brasília)",
+      "type": "string"
+    },
+    "source": {
+      "description": "Fonte oficial do dado (API do IBGE consultada)",
+      "type": "string"
+    },
+    "source_url": {
+      "description": "URL canônica que reproduz a consulta",
+      "type": "string"
+    }
+  },
+  "required": [
+    "source",
+    "source_url",
+    "data_vintage",
+    "retrieved_at",
+    "citation",
+    "license"
+  ],
+  "type": "object"
+}

addedOutput schema / properties / ranking / properties / sexo / anyOf

Added value: +[
+  {
+    "type": "string"
+  },
+  {
+    "type": "null"
+  }
+]

removedOutput schema / properties / ranking / properties / sexo / type
```
Removed value: -[
-  "string",
-  "null"
-]
```

changedOutput schema / required

Previous value: -[
-  "tipo"
-]New value: +[
+  "tipo",
+  "provenance",
+  "attribution"
+]

Changed1 schema field changedv3.0.0Jun 20, 2026

changedOutput schema / (root)

Previous value: -nullNew value: +{
+  "$schema": "http://json-schema.org/draft-07/schema#",
+  "additionalProperties": false,
+  "properties": {
+    "frequencia": {
+      "description": "Resultados de frequência (presente quando tipo='frequencia')",
+      "items": {
+        "additionalProperties": false,
+        "properties": {
+          "localidade": {
+            "description": "Código IBGE da localidade (ou BR para Brasil)",
+            "type": "string"
+          },
+          "nome": {
+            "description": "Nome consultado",
+            "type": "string"
+          },
+          "periodos": {
+            "description": "Frequência do nome por período",
+            "items": {
+              "additionalProperties": false,
+              "properties": {
+                "frequencia": {
+                  "description": "Frequência de registros do nome no período",
+                  "type": "number"
+                },
+                "periodo": {
+                  "description": "Período/década (ex: '1930[', '1990,2000[')",
+                  "type": "string"
+                }
+              },
+              "required": [
+                "periodo",
+                "frequencia"
+              ],
+              "type": "object"
+            },
+            "type": "array"
+          },
+          "sexo": {
+            "description": "Sexo do nome: M, F ou nulo",
+            "type": [
+              "string",
+              "null"
+            ]
+          },
+          "total": {
+            "description": "Soma das frequências de todos os períodos",
+            "type": "number"
+          }
+        },
+        "required": [
+          "nome",
+          "localidade",
+          "periodos",
+          "total"
+        ],
+        "type": "object"
+      },
+      "type": "array"
+    },
+    "ranking": {
+      "additionalProperties": false,
+      "description": "Resultado do ranking (presente quando tipo='ranking')",
+      "properties": {
+        "decada": {
+          "description": "Década do ranking, quando informada",
+          "type": "number"
+        },
+        "itens": {
+          "description": "Itens do ranking, limitados pelo parâmetro 'limite'",
+          "items": {
+            "additionalProperties": false,
+            "properties": {
+              "frequencia": {
+                "description": "Frequência de registros do nome",
+                "type": "number"
+              },
+              "nome": {
+                "description": "Nome",
+                "type": "string"
+              },
+              "ranking": {
+                "description": "Posição no ranking",
+                "type": "number"
+              }
+            },
+            "required": [
+              "ranking",
+              "nome",
+              "frequencia"
+            ],
+            "type": "object"
+          },
+          "type": "array"
+        },
+        "localidade": {
+          "description": "Código IBGE da localidade (ou BR para Brasil)",
+          "type": "string"
+        },
+        "sexo": {
+          "description": "Sexo do ranking: M, F ou nulo",
+          "type": [
+            "string",
+            "null"
+          ]
+        }
+      },
+      "required": [
+        "localidade",
+        "itens"
+      ],
+      "type": "object"
+    },
+    "tipo": {
+      "description": "Tipo da consulta realizada",
+      "enum": [
+        "frequencia",
+        "ranking"
+      ],
+      "type": "string"
+    }
+  },
+  "required": [
+    "tipo"
+  ],
+  "type": "object"
+}

First observedv1.0.0Jan 23, 2026

TDQS

A4.1/5.0

Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare read-only, idempotent, non-destructive, open-world, so the redundant 'read-only and idempotent' line earns nothing. However, the description adds genuinely new context: the live GET against the public IBGE Nomes (Censo) API, the Markdown-table return shape, and the 1930–2010 decade constraint that the schema does not state.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Front-loaded one-line summary followed by numbered features, examples, and a behavior note — well organized and scannable. Minor waste from the read-only/idempotent sentence duplicating annotations and some repeated param hints, but nothing egregious.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

An output schema exists, so return values need not be detailed beyond the Markdown-table note. Both query modes, their required inputs, and the decade range are covered, making the definition sufficient for correct invocation; only minor edge cases (e.g., locality code validation) are left implicit.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

With 100% schema description coverage, the schema already documents each parameter and even tags them by tipo ('Para tipo=frequencia', 'Para tipo=ranking'), including comma-separated names and the limit default. The description largely restates those bindings and the decade example list, adding only the 1930–2010 range, so the baseline 3 is correct.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource ('Queries name frequency and rankings in Brazil (IBGE)') and enumerates the two distinct query modes. The resource is unique among the ibge_* siblings, so an agent can immediately tell this tool apart from geography/indicator/calendar tools without opening any schema.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The feature breakdown plus four worked examples make the when-to-use for each mode (tipo='frequencia' vs tipo='ranking') unambiguous. It does not name or exclude any sibling alternative, and gives no explicit when-not-to-use, so it stops short of a 5.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.