Skip to main content
Glama

ATC Class Members

atc_members
Read-onlyIdempotent

List the drugs (substances) that belong to an ATC class.

Use this tool to:

  • Enumerate all members of a therapeutic class (e.g., "A10BA" → metformin, phenformin)

  • Build a list of drugs sharing a pharmacological mechanism

  • Explore an ATC subtree at any level

Each member includes its substance-level (7-char) ATC code via source_atc_code, useful for disambiguation when the queried class is at level 1-4. RxNorm's catalog is US-centric; the ATC class names and codes themselves are international.

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
atc_codeYesATC code at any level. Higher levels (1-4) return all member substances; level 5 returns the single substance.

Output Schema

TableJSON Schema
NameRequiredDescriptionDefault
membersYes
atc_codeYes
provenanceYesProvenance block (contract v1.1): source, URL, data vintage, extraction instant, origin diagnostics, citation, license
attributionYesCanonical source URLs of this response (attribution list)

Schema Changelog

Changes observed during successful MCP inspections.

  1. Changed3 schema fields changed
    • changedOutput schema / properties / provenance / description
      Previous value: -"Provenance block (contract v1.0): source, URL, data vintage, extraction instant, citation, license"New value: +"Provenance block (contract v1.1): source, URL, data vintage, extraction instant, origin diagnostics, citation, license"
    • addedOutput schema / properties / provenance / properties / retrieval
      Added value: +{
      +  "anyOf": [
      +    {
      +      "additionalProperties": false,
      +      "properties": {
      +        "anomalies": {
      +          "description": "Anomalias superadas até o sucesso, somadas por classe, em ordem fixa; [] se nenhuma",
      +          "items": {
      +            "additionalProperties": false,
      +            "properties": {
      +              "count": {
      +                "description": "Ocorrências desta classe na chamada",
      +                "maximum": 9007199254740991,
      +                "minimum": 1,
      +                "type": "integer"
      +              },
      +              "kind": {
      +                "description": "Classe da anomalia (vocabulário fechado do contrato)",
      +                "enum": [
      +                  "timeout",
      +                  "network",
      +                  "http_4xx",
      +                  "http_5xx",
      +                  "rate_limited",
      +                  "malformed_body"
      +                ],
      +                "type": "string"
      +              }
      +            },
      +            "required": [
      +              "kind",
      +              "count"
      +            ],
      +            "type": "object"
      +          },
      +          "type": "array"
      +        },
      +        "attempts": {
      +          "description": "Tentativas somadas, incluindo as repetidas (>= requests)",
      +          "maximum": 9007199254740991,
      +          "minimum": 1,
      +          "type": "integer"
      +        },
      +        "requests": {
      +          "description": "Idas distintas à origem que compõem esta resposta (fatias, páginas)",
      +          "maximum": 9007199254740991,
      +          "minimum": 1,
      +          "type": "integer"
      +        },
      +        "unstable": {
      +          "description": "true se houve repetição (attempts > requests) ou alguma anomalia",
      +          "type": "boolean"
      +        }
      +      },
      +      "required": [
      +        "requests",
      +        "attempts",
      +        "anomalies",
      +        "unstable"
      +      ],
      +      "type": "object"
      +    },
      +    {
      +      "type": "null"
      +    }
      +  ],
      +  "description": "Origin diagnostics of THIS source in this call (contract v1.1): requests made to the upstream, attempts summed across retries, anomalies worked around (kind + count); unstable=true when any anomaly happened. null when nothing was measured (bundled dataset, or response served entirely from cache)"
      +}
    • changedOutput schema / properties / provenance / required
      Previous value: -[
      -  "source",
      -  "source_url",
      -  "data_vintage",
      -  "retrieved_at",
      -  "citation",
      -  "license"
      -]New value: +[
      +  "source",
      +  "source_url",
      +  "data_vintage",
      +  "retrieved_at",
      +  "retrieval",
      +  "citation",
      +  "license"
      +]
  2. Changed1 schema field changed
    • addedInput schema / additionalProperties
      Added value: +false
  3. First observed

TDQS

A4.1/5.0
Behavior4/5

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

Annotations already cover safety (readOnly, idempotent, non-destructive, openWorld), so the description earns credit for adding non-obvious context: that each member carries a substance-level source_atc_code for disambiguation, and that RxNorm's catalog is US-centric while ATC names/codes are international. It does not mention result volume or pagination for large classes, which would be the next useful disclosure.

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 purpose, followed by a scannable bullet list and a closing caveat sentence; nearly every line earns its place. Slight redundancy between 'enumerate all members' and 'explore an ATC subtree at any level', which overlap conceptually.

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?

For a single-parameter read tool with an output schema present, the description supplies purpose, usage contexts, parameter levels, an output field note, and a data-provenance caveat - enough to call it correctly. What is missing is only operational detail such as result size for high-level classes.

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?

Schema description coverage is 100% and the schema already states the level 1-4 vs level-5 return behavior, so the baseline is 3. The description reinforces this with the 'A10BA' example but adds little syntax or format detail the schema does not already carry.

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?

Specific verb + resource ('List the drugs (substances) that belong to an ATC class') with a concrete example ('A10BA' -> metformin, phenformin). The subtree/level framing implicitly separates it from atc_classify (drug -> class) and atc_lookup (code -> meaning), so an agent can route without opening schemas.

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 'Use this tool to:' block gives three clear contexts (enumerate class members, build mechanism-shared drug lists, explore a subtree). It does not name any sibling as the alternative or state when NOT to use it, so routing against atc_lookup/atc_classify is left to inference.

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

Try in Browser

Glama MCP Gateway

Add one secure layer between your agents and this server.