Scholar MCP Server

fetch_pdf_text_unpaywall_tool

Resolve any DOI to its best available PDF from Unpaywall and extract the full text using PyMuPDF.

Instructions

An all-in-one bypass. Takes a DOI, resolves its best PDF on Unpaywall, and directly downloads/extracts the text using PyMuPDF.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "doi": "<doi>"
    },
    "name": "fetch_pdf_text_unpaywall_tool"
  }
}

Input Schema

Name	Required	Description	Default
`doi`	Yes

Output Schema

Name	Required	Description	Default
`result`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

First observedv1.0.0Jul 28, 2026

TDQS

A3.7/5.0

Behavior3/5

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

No annotations are provided; the description discloses the action (resolves PDF, extracts text) and uses PyMuPDF. However, it omits failure modes (e.g., no PDF found), authentication needs, and rate limits.

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?

The description is a single sentence that front-loads the purpose with 'An all-in-one bypass'. It is concise but could benefit from clearer structure.

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?

Given the simple parameter set (only DOI) and the existence of an output schema, the description covers the essential action. However, missing error handling details slightly reduces completeness.

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?

With 0% schema coverage, the description adds value by stating 'Takes a DOI'. For a single parameter, this clarifies its role, though format expectations are not detailed.

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?

The description clearly states the tool's verb ('resolves', 'downloads/extracts'), resource ('PDF via Unpaywall'), and distinguishes from siblings like get_unpaywall_link_tool and fetch_pdf_text_scihub_tool.

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

Usage Guidelines2/5

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

No explicit guidance on when to use this tool vs alternatives, prerequisites (e.g., valid DOI), or rate limits. The description only implies usage for Unpaywall access.

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