pubmed-search-mcp

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get_citation_metrics

Read-onlyIdempotent

Retrieve citation metrics from NIH iCite for PubMed articles, including citation count, RCR, percentile, and citations per year. Sort and filter results.

Instructions

Get citation metrics from NIH iCite for articles.

Returns field-normalized citation data including:

citation_count: Total number of citations
relative_citation_ratio (RCR): Field-normalized metric (1.0 = average)
nih_percentile: Percentile ranking (0-100)
citations_per_year: Citation velocity
apt: Approximate Potential to Translate (clinical relevance 0-1)

Can sort and filter results by citation metrics.

Args: pmids: PubMed IDs - accepts multiple formats: - "12345678,87654321" (comma-separated) - ["12345678", "87654321"] (list) - '["12345678", "87654321"]' (JSON array string) - "PMID:12345678" (with prefix) - "last" to use PMIDs from the last search Batches are fail-closed and limited to 1,000 items before deduplication. sort_by: Metric to sort by: - "citation_count": Raw citation count (default) - "relative_citation_ratio": Field-normalized (recommended) - "nih_percentile": Percentile ranking - "citations_per_year": Citation velocity min_citations: Filter out articles with fewer citations min_rcr: Filter out articles with RCR below threshold (e.g., 1.0 = average) min_percentile: Filter out articles below percentile (e.g., 50 = top half)

Returns: Articles with citation metrics, sorted and filtered as requested. iCite transport or response failures return an explicit retryable error and are never rendered as an empty/unindexed result.

Input Schema

TableJSON Schema

Name	Required	Default
`pmids`	Yes
`min_rcr`	No
`sort_by`	No	citation_count
`min_citations`	No
`output_format`	No	markdown
`min_percentile`	No

Schema Changelog

Changes observed during successful MCP inspections.

Changed11 schema fields changedv0.7.7Oct 7, 2026

changedInput schema / properties / min_citations / anyOf

Previous value: -[
-  {
-    "maximum": 2000000000,
-    "minimum": 0,
-    "type": "integer"
-  },
-  {
-    "type": "null"
-  }
-]New value: +[
+  {
+    "maximum": 2000000000,
+    "minimum": 0,
+    "type": "integer"
+  },
+  {
+    "type": "null"
+  },
+  {
+    "description": "ASCII decimal integer; the integer branch's bounds apply after conversion.",
+    "maxLength": 32,
+    "pattern": "^[ \\t\\r\\n]*-?(?:0|[1-9][0-9]*)[ \\t\\r\\n]*$",
+    "type": "string"
+  }
+]

changedInput schema / properties / min_percentile / anyOf

Previous value: -[
-  {
-    "maximum": 100,
-    "minimum": 0,
-    "type": "number"
-  },
-  {
-    "type": "null"
-  }
-]New value: +[
+  {
+    "maximum": 100,
+    "minimum": 0,
+    "type": "number"
+  },
+  {
+    "type": "null"
+  },
+  {
+    "description": "Finite decimal number; the numeric branch's bounds apply after conversion.",
+    "maxLength": 64,
+    "pattern": "^[ \\t\\r\\n]*-?(?:0|[1-9][0-9]*)(?:\\.[0-9]+)?[ \\t\\r\\n]*$",
+    "type": "string"
+  }
+]

changedInput schema / properties / min_rcr / anyOf

Previous value: -[
-  {
-    "maximum": 1000000,
-    "minimum": 0,
-    "type": "number"
-  },
-  {
-    "type": "null"
-  }
-]New value: +[
+  {
+    "maximum": 1000000,
+    "minimum": 0,
+    "type": "number"
+  },
+  {
+    "type": "null"
+  },
+  {
+    "description": "Finite decimal number; the numeric branch's bounds apply after conversion.",
+    "maxLength": 64,
+    "pattern": "^[ \\t\\r\\n]*-?(?:0|[1-9][0-9]*)(?:\\.[0-9]+)?[ \\t\\r\\n]*$",
+    "type": "string"
+  }
+]

addedInput schema / properties / output_format / anyOf

Added value: +[
+  {
+    "default": "markdown",
+    "enum": [
+      "markdown",
+      "json",
+      "toon"
+    ],
+    "title": "Output Format",
+    "type": "string"
+  },
+  {
+    "pattern": "^[ \\t\\r\\n]*(?:[mM][aA][rR][kK][dD][oO][wW][nN]|[jJ][sS][oO][nN]|[tT][oO][oO][nN])[ \\t\\r\\n]*$",
+    "type": "string"
+  }
+]

removedInput schema / properties / output_format / enum

Removed value: -[
-  "markdown",
-  "json",
-  "toon"
-]

removedInput schema / properties / output_format / type
```
Removed value: -"string"
```

changedInput schema / properties / pmids / anyOf

Previous value: -[
-  {
-    "maxLength": 100000,
-    "minLength": 1,
-    "type": "string"
-  },
-  {
-    "items": {
-      "maxLength": 512,
-      "minLength": 1,
-      "type": "string"
-    },
-    "maxItems": 1000,
-    "minItems": 1,
-    "type": "array"
-  }
-]New value: +[
+  {
+    "description": "Complete PMID(s): delimited text, JSON string array, or Markdown list; optional JSON code fence. last only where supported.",
+    "examples": [
+      "33053718,36170657",
+      "[\"33053718\",\"36170657\"]",
+      "- 33053718\n- 36170657"
+    ],
+    "format": "pubmed-pmid-batch",
+    "maxLength": 100000,
+    "minLength": 1,
+    "type": "string"
+  },
+  {
+    "items": {
+      "description": "One PMID string, or last as the sole batch item for tools supporting session reuse.",
+      "examples": [
+        "33053718"
+      ],
+      "format": "pubmed-pmid",
+      "maxLength": 512,
+      "minLength": 1,
+      "type": "string",
+      "x-pubmed-input": "pmid"
+    },
+    "maxItems": 1000,
+    "minItems": 1,
+    "type": "array"
+  }
+]

addedInput schema / properties / pmids / x-pubmed-input
```
Added value: +"pmid_batch"
```

addedInput schema / properties / sort_by / anyOf

Added value: +[
+  {
+    "default": "citation_count",
+    "enum": [
+      "citation_count",
+      "relative_citation_ratio",
+      "nih_percentile",
+      "citations_per_year"
+    ],
+    "title": "Sort By",
+    "type": "string"
+  },
+  {
+    "pattern": "^[ \\t\\r\\n]*(?:[cC][iI][tT][aA][tT][iI][oO][nN]_[cC][oO][uU][nN][tT]|[rR][eE][lL][aA][tT][iI][vV][eE]_[cC][iI][tT][aA][tT][iI][oO][nN]_[rR][aA][tT][iI][oO]|[nN][iI][hH]_[pP][eE][rR][cC][eE][nN][tT][iI][lL][eE]|[cC][iI][tT][aA][tT][iI][oO][nN][sS]_[pP][eE][rR]_[yY][eE][aA][rR])[ \\t\\r\\n]*$",
+    "type": "string"
+  }
+]

removedInput schema / properties / sort_by / enum

Removed value: -[
-  "citation_count",
-  "relative_citation_ratio",
-  "nih_percentile",
-  "citations_per_year"
-]

removedInput schema / properties / sort_by / type
```
Removed value: -"string"
```

Changed7 schema fields changedv0.7.2Sep 13, 2026

addedInput schema / additionalProperties
```
Added value: +false
```

changedInput schema / properties / min_citations / anyOf

Previous value: -[
-  {
-    "type": "integer"
-  },
-  {
-    "type": "null"
-  }
-]New value: +[
+  {
+    "maximum": 2000000000,
+    "minimum": 0,
+    "type": "integer"
+  },
+  {
+    "type": "null"
+  }
+]

changedInput schema / properties / min_percentile / anyOf

Previous value: -[
-  {
-    "type": "number"
-  },
-  {
-    "type": "null"
-  }
-]New value: +[
+  {
+    "maximum": 100,
+    "minimum": 0,
+    "type": "number"
+  },
+  {
+    "type": "null"
+  }
+]

changedInput schema / properties / min_rcr / anyOf

Previous value: -[
-  {
-    "type": "number"
-  },
-  {
-    "type": "null"
-  }
-]New value: +[
+  {
+    "maximum": 1000000,
+    "minimum": 0,
+    "type": "number"
+  },
+  {
+    "type": "null"
+  }
+]

changedInput schema / properties / pmids / anyOf

Previous value: -[
-  {
-    "type": "string"
-  },
-  {
-    "items": {},
-    "type": "array"
-  },
-  {
-    "type": "integer"
-  }
-]New value: +[
+  {
+    "maxLength": 100000,
+    "minLength": 1,
+    "type": "string"
+  },
+  {
+    "items": {
+      "maxLength": 512,
+      "minLength": 1,
+      "type": "string"
+    },
+    "maxItems": 1000,
+    "minItems": 1,
+    "type": "array"
+  }
+]

addedInput schema / properties / sort_by / enum

Added value: +[
+  "citation_count",
+  "relative_citation_ratio",
+  "nih_percentile",
+  "citations_per_year"
+]

changedOutput schema / (root)

Previous value: -{
-  "properties": {
-    "result": {
-      "title": "Result",
-      "type": "string"
-    }
-  },
-  "required": [
-    "result"
-  ],
-  "title": "get_citation_metricsOutput",
-  "type": "object"
-}New value: +null

First observedv0.5.16Jun 19, 2026

TDQS

A3.8/5.0

Behavior4/5

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

Annotations already declare readOnlyHint=true, idempotentHint=true and destructiveHint=false, so safety is covered. The description adds real behavior beyond that: batching is fail-closed and capped at 1,000 items before deduplication, and iCite transport/response failures surface as an explicit retryable error rather than an empty result. Rate limits and auth requirements are not mentioned.

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 with what the tool returns, then Args, then Returns, using headers and bullets so an agent can scan it. The metric glossary earns its space because those fields are non-obvious, but the duplicated sort_by listing (once under returns, once under args) adds some redundancy.

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?

With no output schema, the description correctly spends space explaining the return fields and their normalization, and it also covers batch limits and failure behavior for a 6-parameter, open-world tool. The omission of output_format and of any statement about ordering direction or result caps keeps it short of fully complete.

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

Parameters4/5

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

Schema description coverage is reported as 0%, so the description carries the burden and mostly does: it documents the multiple PMID input formats (comma-separated, list, JSON array string, 'PMID:' prefix, 'last'), the batch cap, every sort_by enum value with meaning, and the semantics of min_citations/min_rcr/min_percentile with example thresholds. The one gap is output_format, which is never mentioned in the prose despite being a real enum parameter.

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

Purpose4/5

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

States a specific verb+resource ('Get citation metrics from NIH iCite for articles') and enumerates exactly which metrics come back, including the meaning of each (RCR, nih_percentile, apt). It is clear what the tool does, but it never names or contrasts itself against plausible siblings such as find_citing_articles or build_citation_tree, leaving the agent to infer the boundary.

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

Usage Guidelines3/5

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

Usage is implied rather than stated: sorting/filtering is described, 'relative_citation_ratio' is marked recommended, and 'last' is noted as reusing PMIDs from the previous search. There is no explicit when-to-use/when-not guidance or named alternative for retrieving citation data by other means, so the agent must infer the context.

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

Deploy Server

get_citation_metrics

Instructions

Input Schema

Schema Changelog

TDQS

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