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Glama

ATC Classification for a Drug

atc_classify
Read-onlyIdempotent

Find a drug's WHO ATC classification by name to get its international code and therapeutic class hierarchy.

Instructions

Look up the WHO ATC (Anatomical Therapeutic Chemical) classification(s) for a drug by name.

Use this tool to:

  • Find the ATC code for a medication (e.g., "metformin" → A10BA02)

  • Identify the therapeutic and pharmacological class hierarchy

  • Cross-reference drugs with their international ATC codes

Returns one entry per ATC code the drug belongs to. A single-ingredient drug typically maps to one substance-level code; combination products map to multiple. ATC codes are international (WHO Collaborating Centre); this tool retrieves them via NLM RxClass.

Input is a drug NAME (brand or generic, English/US naming as in RxNorm). A name RxNorm does not recognize, or a drug without an ATC mapping, returns an empty matches list with an explanatory note — not an error; try the generic name, or resolve the name first with rxnorm_search.

Which ATC tool: start here when you have a drug name; use atc_lookup when you already have a class code (level 1-4, e.g. "A10BA") and want its name; use atc_members to list the drugs inside a class.

Input Schema

NameRequiredDescriptionDefault
drug_nameYesDrug name to classify (brand or generic, e.g., "metformin")

Output Schema

NameRequiredDescriptionDefault
matchesYesATC classes NLM RxClass assigns to the drug, one entry per RxNorm concept and ATC class pair; empty when the drug is unknown or has no ATC mapping.
drug_nameYesThe drug name as submitted.
provenanceYesProvenance block: 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. Changed2 schema fields changedv2.4.0
    • addedOutput schema / properties / drug_name / description
      Added value: +"The drug name as submitted."
    • addedOutput schema / properties / matches / description
      Added value: +"ATC classes NLM RxClass assigns to the drug, one entry per RxNorm concept and ATC class pair; empty when the drug is unknown or has no ATC mapping."
  2. Changed7 schema fields changedv2.3.0
    • changedOutput schema / properties / provenance / description
      Previous value: -"Provenance block (contract v1.1): source, URL, data vintage, extraction instant, origin diagnostics, citation, license"New value: +"Provenance block: source, URL, data vintage, extraction instant, origin diagnostics, citation, license"
    • addedOutput schema / properties / provenance / properties / derivation_note
      Added value: +{
      +  "description": "What this server computed; present together with derived",
      +  "type": "string"
      +}
    • addedOutput schema / properties / provenance / properties / derived
      Added value: +{
      +  "description": "Present (true) only when this server computed the value (e.g. a ranking or summary statistics) instead of passing on what the source returned",
      +  "type": "boolean"
      +}
    • changedOutput schema / properties / provenance / properties / field_sources / description
      Previous value: -"Present only when the response joins parts from different origins or extraction instants (contract v1.2): for each group of fields, its URL, extraction instant and whether it came from cache. Absent in single-origin responses"New value: +"Present only when the response joins parts from different origins or extraction instants: for each group of fields, its URL, extraction instant and whether it came from cache. Absent in single-origin responses"
    • addedOutput schema / properties / provenance / properties / notices
      Added value: +{
      +  "description": "Caveats the source publishes about the data, verbatim (license statements are not repeated here; see the info://licenses resource). Absent when there is none",
      +  "items": {
      +    "type": "string"
      +  },
      +  "minItems": 1,
      +  "type": "array"
      +}
    • changedOutput schema / properties / provenance / properties / retrieval / description
      Previous value: -"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)"New value: +"Origin diagnostics of THIS source in this call: 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)"
    • addedOutput schema / properties / provenance / properties / revision
      Added value: +{
      +  "additionalProperties": false,
      +  "description": "Whether the data can still change at the source: current = the version in force, the source may revise it; provisional = preliminary; final = will not change. Absent when unknown",
      +  "properties": {
      +    "note": {
      +      "description": "O específico da fonte: o que revisa, quando, por quê",
      +      "type": [
      +        "string",
      +        "null"
      +      ]
      +    },
      +    "status": {
      +      "description": "current = versão vigente, a fonte pode revisá-la; provisional = preliminar, incompleta ou sujeita a mudança (não compare como se fosse fechada); final = não muda mais, declarado pela fonte",
      +      "enum": [
      +        "current",
      +        "provisional",
      +        "final"
      +      ],
      +      "type": "string"
      +    }
      +  },
      +  "required": [
      +    "status",
      +    "note"
      +  ],
      +  "type": "object"
      +}
  3. Changed1 schema field changedv2.1.1
    • addedOutput schema / properties / provenance / properties / field_sources
      Added value: +{
      +  "description": "Present only when the response joins parts from different origins or extraction instants (contract v1.2): for each group of fields, its URL, extraction instant and whether it came from cache. Absent in single-origin responses",
      +  "items": {
      +    "additionalProperties": false,
      +    "description": "Proveniência de um grupo de campos da resposta: de onde veio e quando foi extraído",
      +    "properties": {
      +      "data_vintage": {
      +        "description": "Vintage/competência da sub-fonte",
      +        "type": [
      +          "string",
      +          "null"
      +        ]
      +      },
      +      "dataset_id": {
      +        "description": "Identificador do conjunto da sub-fonte",
      +        "type": [
      +          "string",
      +          "null"
      +        ]
      +      },
      +      "fields": {
      +        "description": "Campos do payload atribuídos a esta sub-fonte",
      +        "items": {
      +          "type": "string"
      +        },
      +        "minItems": 1,
      +        "type": "array"
      +      },
      +      "retrieved_at": {
      +        "description": "ISO-8601 da extração desta sub-fonte na origem",
      +        "type": [
      +          "string",
      +          "null"
      +        ]
      +      },
      +      "served_from_cache": {
      +        "description": "true se esta sub-fonte veio do cache do servidor (retrieved_at é o da extração original); false se foi buscada nesta chamada; null se o servidor não distingue",
      +        "type": [
      +          "boolean",
      +          "null"
      +        ]
      +      },
      +      "source_url": {
      +        "description": "URL canônica da sub-fonte que originou estes campos",
      +        "type": "string"
      +      }
      +    },
      +    "required": [
      +      "fields",
      +      "source_url",
      +      "dataset_id",
      +      "data_vintage",
      +      "retrieved_at"
      +    ],
      +    "type": "object"
      +  },
      +  "minItems": 1,
      +  "type": "array"
      +}
  4. Changed3 schema fields changedv1.15.0
    • 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"
      +]
  5. Changed1 schema field changedv1.11.0
    • addedInput schema / additionalProperties
      Added value: +false
  6. Changed4 schema fields changedv1.9.1
    • 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"
      +]
  7. Changed3 schema fields changedv1.8.0
    • addedOutput schema / properties / attribution
      Added value: +{
      +  "description": "Canonical source URLs of this response (attribution list)",
      +  "items": {
      +    "type": "string"
      +  },
      +  "type": "array"
      +}
    • addedOutput schema / properties / provenance
      Added value: +{
      +  "additionalProperties": false,
      +  "description": "Provenance block (contract v1.0): source, URL, data vintage, extraction instant, citation, license",
      +  "properties": {
      +    "citation": {
      +      "description": "Ready-to-use citation/attribution string",
      +      "type": "string"
      +    },
      +    "data_vintage": {
      +      "anyOf": [
      +        {
      +          "type": "string"
      +        },
      +        {
      +          "type": "null"
      +        }
      +      ],
      +      "description": "Version/release of the data as exposed by the source; null when not exposed"
      +    },
      +    "license": {
      +      "anyOf": [
      +        {
      +          "type": "string"
      +        },
      +        {
      +          "type": "null"
      +        }
      +      ],
      +      "description": "License / legal regime of the data"
      +    },
      +    "retrieved_at": {
      +      "description": "Real instant of the upstream extraction (ISO-8601, UTC). Responses served from cache keep the ORIGINAL fetch instant.",
      +      "type": "string"
      +    },
      +    "source": {
      +      "description": "Official upstream source of this data",
      +      "type": "string"
      +    },
      +    "source_url": {
      +      "description": "Canonical URL of the source (API base or dataset release)",
      +      "type": "string"
      +    }
      +  },
      +  "required": [
      +    "source",
      +    "source_url",
      +    "data_vintage",
      +    "retrieved_at",
      +    "citation",
      +    "license"
      +  ],
      +  "type": "object"
      +}
    • changedOutput schema / required
      Previous value: -[
      -  "drug_name",
      -  "matches"
      -]New value: +[
      +  "drug_name",
      +  "matches",
      +  "provenance",
      +  "attribution"
      +]
  8. Changed1 schema field changedv1.5.7
    • removedInput schema / additionalProperties
      Removed value: -false
  9. First observedv1.2.1

TDQS

A5/5.0
Behavior5/5

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

Annotations already cover the safety profile (readOnly, idempotent, openWorld, non-destructive), and the description goes well beyond them: cardinality of results (one entry per ATC code, single-ingredient vs combination), the fact that an unresolved name or unmapped drug returns an empty `matches` list rather than an error, and the retrieval source (NLM RxClass, WHO codes). That empty-vs-error distinction is exactly the behavioral detail an agent cannot get from structured fields.

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

Conciseness5/5

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

Front-loaded purpose sentence, then scannable bullets for use cases, then return semantics, then input caveats, then sibling routing. Length is justified by the routing decision it resolves; no sentence merely restates the title or the schema.

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

Completeness5/5

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

Single-parameter, read-only lookup with an output schema present — the description need not explain return structure, yet it still characterizes result cardinality and the empty-result case. Nothing an agent needs to invoke it correctly or interpret a null result is missing.

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

Parameters5/5

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

Schema coverage is 100%, so baseline is 3; the description earns more by adding naming semantics the schema lacks: brand or generic, English/US naming as in RxNorm, and what happens on a miss. It also warns against resolving outcomes as errors, which shapes how the parameter value should be constructed.

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 and resource ("Look up WHO ATC classification(s) for a drug by name") with a concrete worked example ("metformin" → A10BA02). The closing "Which ATC tool" paragraph explicitly separates it from atc_lookup and atc_members, so an agent can disambiguate 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 Guidelines5/5

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

States exactly when to start here ("when you have a drug name") and names the two alternatives with the precise condition that selects each (class code level 1-4 → atc_lookup; list drugs in a class → atc_members). It even prescribes a fallback path ("resolve the name first with rxnorm_search") for the empty-result case.

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