# `pubmed__pubmed_format_citations`
**Pubmed Format Citations**
Get formatted citations for PubMed articles in one or more formats (apa, mla, bibtex, ris, vancouver). Pass a single format as a string or multiple as an array.
- Server: [PubMed](https://gateway.mcpharbor.dev/docs/servers/pubmed) (`dev.mcpharbor.gateway/pubmed`)
- Price per call: $0.0001 (100 micro-USD); only tools/call is charged
- Endpoint: `https://gateway.mcpharbor.dev/mcp` or `https://gateway.mcpharbor.dev/mcp/pubmed`
- Upstream tool: exposed by the provider; called through this gateway as `pubmed__pubmed_format_citations`
- Provider terms: (verified 2026-09-19)
- Upstream API documentation:
- Rate limit: 150 requests per minute
- Attribution required: NCBI's Disclaimer and Copyright notice must be evident to users of your product
## Parameters
- `format` (any, optional): Citation format(s) to generate — single style as a string or multiple as an array. Allowed values: apa, mla, bibtex, ris, vancouver. Default: `apa`.
- `pmids` (array, required): PubMed IDs to cite
## Example call
Request headers and body:
```http
POST /mcp HTTP/1.1
Host: gateway.mcpharbor.dev
Authorization: Bearer
Content-Type: application/json
Accept: application/json, text/event-stream
MCP-Protocol-Version: 2026-07-28
Mcp-Method: tools/call
Mcp-Name: pubmed__pubmed_format_citations
```
```json
{
"id": 1,
"jsonrpc": "2.0",
"method": "tools/call",
"params": {
"_meta": {
"io.modelcontextprotocol/clientCapabilities": {},
"io.modelcontextprotocol/clientInfo": {
"name": "example-agent",
"version": "1.0.0"
},
"io.modelcontextprotocol/protocolVersion": "2026-07-28"
},
"arguments": {
"pmids": []
},
"name": "pubmed__pubmed_format_citations"
}
}
```
A successful response:
```json
{
"id": 1,
"jsonrpc": "2.0",
"result": {
"_meta": {
"dev.mcpharbor.gateway/call": {
"chargedMicroUsd": 100,
"id": ""
}
},
"content": [
{
"text": "",
"type": "text"
}
],
"resultType": "complete"
}
}
```
This call costs $0.0001 (100 micro-USD). Reading this page and listing the tool cost nothing.
The `dev.mcpharbor.gateway/call` record in the result is the receipt for that charge. Each
POST is metered separately, so sending the same call again buys another one: see
[agent.txt](https://gateway.mcpharbor.dev/agent.txt), section 7, before retrying.
## Attribution
This provider requires the attribution below wherever you use results from its tools.
Reproduce it verbatim:
> NCBI's Disclaimer and Copyright notice must be evident to users of your product
## Tool definition
Exactly as `tools/list` returns it (free):
```json
{
"_meta": {
"dev.mcpharbor.gateway/pricing": {
"currency": "USD",
"pricePerCallMicroUsd": 100
}
},
"annotations": {
"openWorldHint": true,
"readOnlyHint": true
},
"description": "Get formatted citations for PubMed articles in one or more formats (apa, mla, bibtex, ris, vancouver). Pass a single format as a string or multiple as an array.",
"inputSchema": {
"$schema": "https://json-schema.org/draft/2020-12/schema",
"additionalProperties": false,
"properties": {
"format": {
"anyOf": [
{
"description": "Single citation style. One of: apa, mla, bibtex, ris, vancouver.",
"enum": [
"apa",
"mla",
"bibtex",
"ris",
"vancouver"
],
"type": "string"
},
{
"description": "Multiple citation styles to generate. Each entry: apa, mla, bibtex, ris, or vancouver.",
"items": {
"enum": [
"apa",
"mla",
"bibtex",
"ris",
"vancouver"
],
"type": "string"
},
"minItems": 1,
"type": "array"
}
],
"default": "apa",
"description": "Citation format(s) to generate — single style as a string or multiple as an array. Allowed values: apa, mla, bibtex, ris, vancouver."
},
"pmids": {
"description": "PubMed IDs to cite",
"items": {
"pattern": "^\\d+$",
"type": "string"
},
"maxItems": 50,
"minItems": 1,
"type": "array"
}
},
"required": [
"pmids"
],
"type": "object"
},
"name": "pubmed__pubmed_format_citations",
"outputSchema": {
"$schema": "https://json-schema.org/draft/2020-12/schema",
"additionalProperties": false,
"anyOf": [
{
"not": {
"required": [
"error"
]
},
"required": [
"citations",
"totalSubmitted",
"totalFormatted"
]
},
{
"required": [
"error"
]
}
],
"properties": {
"citations": {
"description": "Citations per article",
"items": {
"additionalProperties": false,
"description": "Citations for a single article",
"properties": {
"citations": {
"additionalProperties": {
"type": "string"
},
"description": "Citations keyed by style",
"propertyNames": {
"type": "string"
},
"type": "object"
},
"pmid": {
"description": "PubMed ID",
"type": "string"
},
"title": {
"description": "Article title",
"type": "string"
}
},
"required": [
"pmid",
"citations"
],
"type": "object"
},
"type": "array"
},
"error": {
"additionalProperties": {},
"description": "Present when the call failed. Absent on success.",
"properties": {
"code": {
"description": "JSON-RPC error code for this failure.",
"maximum": 9007199254740991,
"minimum": -9007199254740991,
"type": "integer"
},
"data": {
"additionalProperties": {},
"properties": {
"reason": {
"description": "Machine-readable failure mode. Declared by this tool: `queue_full`: Local NCBI request queue is at capacity. `ncbi_unreachable`: NCBI E-utilities is unreachable after all retry attempts. `ncbi_deadline_exceeded`: Total request deadline expired before NCBI returned a response. `ncbi_invalid_response`: NCBI returned a body that could not be parsed (invalid XML/JSON). `ncbi_resource_not_found`: NCBI returned a structured \"not found\" error for the requested ID(s). Other values are possible when a failure originates below the handler.",
"examples": [
"queue_full",
"ncbi_unreachable",
"ncbi_deadline_exceeded",
"ncbi_invalid_response",
"ncbi_resource_not_found"
],
"type": "string"
},
"recovery": {
"additionalProperties": {},
"description": "Actionable next step for the caller.",
"properties": {
"hint": {
"type": "string"
}
},
"required": [
"hint"
],
"type": "object"
},
"retryable": {
"description": "Whether retrying may succeed.",
"type": "boolean"
}
},
"type": "object"
},
"message": {
"description": "Human-readable description of what went wrong.",
"type": "string"
}
},
"required": [
"code",
"message"
],
"type": "object"
},
"notice": {
"description": "Optional guidance when no citations were produced — points to discovery tools. Absent when at least one citation was produced.",
"type": "string"
},
"totalFormatted": {
"description": "Number of PMIDs successfully formatted",
"type": "number"
},
"totalSubmitted": {
"description": "Number of PMIDs submitted for citation formatting",
"type": "number"
},
"unavailablePmids": {
"description": "PMIDs PubMed returned no record for, so nothing could be cited for them. That is all this reports: PubMed omits a PMID it does not recognize silently, with no error and no reason, so the absence says nothing about whether the PMID exists. Use `pubmed_search_articles` to find PMIDs that do resolve.",
"items": {
"type": "string"
},
"type": "array"
}
},
"type": "object"
},
"title": "Pubmed Format Citations"
}
```