What is paper-search?

A command-line tool for finding, downloading, and reading academic papers from sources such as arXiv, PubMed, and bioRxiv. BioRxiv is a website where scientists share biology research papers before formal journal review.

Searching literature with source or year filters, listing available sources, downloading PDFs, and reading their text.

It brings searches across many research databases into one interface and can extract paper text after downloading it.

paper-search — Skill for Claude Code and Codex by Nehra-Amaterasu

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent

npx skills add Nehra-Amaterasu/paper-search-mcp --skill claude-code

Clone the repo

git clone --depth 1 https://github.com/Nehra-Amaterasu/paper-search-mcp

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

README.md

[![agentmods](https://agentmods.dev/badge/skills/nehra-amaterasu/paper-search-mcp/claude-code/github.svg)](https://agentmods.dev/skills/nehra-amaterasu/paper-search-mcp/claude-code)

Your own site

<a href="https://agentmods.dev/skills/nehra-amaterasu/paper-search-mcp/claude-code"><img src="https://agentmods.dev/badge/skills/nehra-amaterasu/paper-search-mcp/claude-code/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

Your own site · 80×15

<a href="https://agentmods.dev/skills/nehra-amaterasu/paper-search-mcp/claude-code"><img src="https://agentmods.dev/badge/skills/nehra-amaterasu/paper-search-mcp/claude-code.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 62 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 1,164 The whole file, excluding the scripts and references it only reads on demand.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.

Origin 100% copy Near-identical to another mod in the catalogue.

Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

Model	Per session	Once invoked
Fable 5.1	$0.00062	$0.01164
Opus 5.5	$0.00025	$0.00466
Sonnet 5.5	$0.00012	$0.00233
Haiku 4.5	$0.00006	$0.00116

Measured 29d ago against content hash e09bb3d7f9dc, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

paper-search scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 29d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

Origin

This is a copy

100% identical to paper-search — 0 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

claude-code/SKILL.md · 100 lines

How it starts

The opening of the file, as written. The whole thing — 100 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Paper Search

Search, download, and read academic papers via the paper-search CLI.

CLI Usage

All commands run via:

paper-search <command> [args]

If paper-search is not available, install it with uv tool install paper-search-mcp. Optional API keys can be configured in ~/.config/paper-search-mcp/.env.

Search

paper-search search "<query>" -n <max_per_source> -s <sources> -y <year>

-n: results per source (default: 5)
-s: comma-separated sources, "fast", "fastest", or "all" (default: all)
--exhaustive: compatibility no-op (broad search is already the default); explicit -s always takes precedence
-y: year filter for Semantic Scholar (e.g. "2020", "2018-2022")

For speed, use -s fast (OpenAlex, Crossref, arXiv, PubMed, Europe PMC; also Semantic Scholar when its API key is nonblank) or -s fastest (OpenAlex and Crossref). Explicit source choices are never expanded, even for DOI queries. Use -s unpaywall for DOI lookup; "all" already includes it. These presets do not enable optional paid sources.

Download PDF

paper-search download <source> <paper_id> [-o ./downloads]

Read (extract text)

paper-search read <source> <paper_id> [-o ./downloads]

List sources

paper-search sources

MCP tools from the CLI

paper-search tool calls the same registered tools as the MCP server, including source-specific options and DOI lookup. Required arguments are positional; optional arguments use kebab-case flags. Boolean flags use --flag and --no-flag; omitted options retain their MCP defaults.

paper-search tool --help
paper-search tool --list  # JSON tool list, schemas, and annotations
paper-search tool search_crossref --help
paper-search tool search_crossref "transformer attention" --filter from-pub-date:2024-01-01 --sort published --order desc --max-results 2
paper-search tool get_crossref_paper_by_doi 10.1038/nature12373
paper-search tool search_iacr "cryptography" --no-fetch-details

Read the full file on GitHub · 100 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

29d ago Changed · +40 lines e09bb3d7f9dc
2mo ago First seen · 60 lines · 62 tokens per session scan A affddf3a4dc4

Subscribe to this mod's changes

paper-search is a skill published in the GitHub repository Nehra-Amaterasu/paper-search-mcp (0 stars, last pushed 1mo ago), licensed MIT. It adds 62 tokens to every session and 1,164 once invoked, about $0.0002 per session on Opus 5.5. A static security scan graded it A with 0 findings. It is 100% identical to paper-search, differing in 0 lines, and is treated as a copy.

Research Scientific

paper-search next to 6 skills from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
paper-searchNehra-Amaterasu/paper-search-mcp	Skill	0	1mo ago	MIT	A	62	Claude Code, Codex
instrument-data-to-allotropeanthropics/knowledge-work-plugins	Skill	35k	yesterday	Apache-2.0	A	123	Claude Code
matlabK-Dense-AI/scientific-agent-skills	Skill	56k	6d ago	MIT	A	44	Claude Code
exploratory-data-analysisK-Dense-AI/scientific-agent-skills	Skill	56k	6d ago	MIT	A	83	Claude Code
phylogeneticsK-Dense-AI/scientific-agent-skills	Skill	56k	6d ago	MIT	A	71	Claude Code, Codex
research-engineerdavila7/claude-code-templates	Skill	33k	today	MIT	A	43	Claude Code, Codex
mapping-to-snomedmaziyarpanahi/openmed	Skill	5.8k	today	Apache-2.0	A	205	Claude Code