# Literature Review > Finds, ranks and reads the literature on a question, the retrieval loop the lead runs itself over OpenAlex, arXiv, Crossref, PubMed and bioRxiv with a fixed budget, deduplication, ranking by topical fit, reading of the load-bearing papers and claim-level links, for related-work sections, prior-art checks, surveys and systematic reviews. Use for "find papers", "what is known about", related work, or a review; escalate to PRISMA screening only when a systematic review is requested. For one quick fact or definition use research-lookup. - Skill: `synthetic-sciences/literature-review` (Agent Skill, multi-file: 3 files) - Install (CLI): `npx skillmds@latest add synthetic-sciences/literature-review` - Raw SKILL.md: https://api.skillmd.com/api/skills/synthetic-sciences/literature-review/raw - Safety review: pending - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Research & Search - License: MIT - Author: synthetic-sciences (https://skillmd.com/u/synthetic-sciences) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/synthetic-sciences/literature-review --- # Literature review You are the retrieval ranker. Run the searches, look at every candidate, decide what is worth reading, and read it before it becomes a claim. Never hand the loop to a worker: the ranking is the judgement, and a worker without the conversation ranks for a different question. ## Non-negotiables 1. **One window, one priority, fixed before the first query.** Recency, historical or default; a date bound only if the question has one. Never widen the window mid-loop to find "the famous paper" the user excluded. 2. **Budget by difficulty.** Rate the question 1–10. Difficulty 1–3 gets the initial round only; 4–7 gets one follow-up round; 8–10 gets two. A round targets one concrete gap (an acronym, a method, a benchmark, a venue), never a rephrasing. 3. **Deduplicate by identifier**, then by DOI or arXiv id, then by normalized title. Prefer the published version's record; note when the arXiv version is the one read. 4. **Rank by topical fit.** The APIs already blend recency and citations into their order; do not apply those preferences a second time, and never compare citation counts across sources. 5. **Read before you claim.** A candidate list may link titles; a finding attributed to a paper requires having read at least its abstract, and its results section for a number. Put the source link right after the sentence it supports. 6. **Stop when coverage is sufficient.** Five to fifteen strong candidates beat forty padded ones. The budget is a cap, not a target. 7. **Size the review to the request.** "A bit of a review", "a quick look", "what is the closest work" is discovery mode: two or three searches, three to five papers read, the concrete missing comparison named, one follow-up search only if that gap matters. The citation ledger, corpus downloads and exhaustive screening are for requests that ask for them. Report substantive findings and blockers, not each retrieval step. ## Workflow - [ ] Frame: the question in the user's terms, the window, the priority, the difficulty. - [ ] Initial round: two or three targeted `literature search` calls, concurrently. - [ ] Deduplicate, rank, and decide whether a follow-up round is warranted. - [ ] `literature read` the 3–5 load-bearing papers (more only if asked). - [ ] Write the synthesis with claim-level links; list what was excluded and why. **Tools.** `literature search` queries OpenAlex and arXiv together, merges records of the same paper, and returns citable candidates (DOI / arXiv id, venue, citations, abstract, whether open full text exists) with a per-source report. `literature read` takes a DOI, arXiv id, URL, local PDF or exact title, caches the open full text once, and returns page-addressed text: the opening pages, a `pages` range, or passages matching `query`. When a source is rate limited the tool has already fallen back where it can (arXiv records also come from OpenAlex and arxiv.org/abs); do not fan out retries, use the alternative it names. Exact API requests, for cases the tool does not cover, are in `skills/core/citations/references/apis.md`. | Field | Default (`literature search`) | Add via `sources` or other tools | | --- | --- | --- | | ML, CS, math, physics | OpenAlex + arXiv | `semantic-scholar` for citation chasing | | Biology, medicine | OpenAlex + arXiv | `pubmed`, `europepmc`, `biorxiv`; `query_pubmed` when available | | Any journal-heavy field | OpenAlex + arXiv | `crossref`; research_search for grey literature and reports | Keyword terms are the user's words and terms observed in results; never invent an acronym expansion. If the query mixes prose with an acronym, run one extra call on the acronym alone in the same round. **Ranking.** Inspect title, abstract, venue and date for every candidate. Keep what answers the question; drop what shares only vocabulary. Within a source the order already carries the requested priority; reorder for topical fit only. Note candidates with code or data. **Follow-up rounds.** One round per concrete gap: a method the results keep citing, a benchmark named but not covered, the seminal paper an abstract points at. Use the source that fits the gap (arXiv keyword for exact terms, OpenAlex for cross-disciplinary reach, `referenced_works` and `cited_by` on OpenAlex for citation chasing). Re-evaluate after each round and stop as soon as coverage holds. **Reading.** `literature read` the 3–5 papers that carry the synthesis; `query` finds the passage, `pages` reads a section. The tool says when only the abstract is open: cite only what the abstract supports, or ask for the PDF. Extract: the claim, the setup that produced it, the number with its uncertainty and conditions, the stated limitations. Do not summarize from snippets. **Synthesis.** Organize by idea, not by paper: what is established, what is contested, what is missing. Each substantive sentence ends with its source link (`https://doi.org/` or `https://arxiv.org/abs/`). Distinguish "X showed" from "X argued" from "X reported in a preprint". Close with the gap the user's work addresses, if that was the purpose. ## Modes - **Discovery** ("find papers", "what should I read"): the ranked list with one line each on why it matters and its link. Stop there; depth is not requested. - **Related work**: the synthesis above, shaped as prose for the manuscript, with the positioning sentence for the user's contribution; the citations skill writes the `.bib`. - **Systematic or scoping review** (only when asked): PRISMA-style protocol first (question, databases, strings, inclusion and exclusion criteria), a screening log with counts at each stage, an evidence table, then the synthesis. `references/database-strategies.md` and `references/search-strategies.md` carry the database-specific syntax and strategy patterns. ## Before you hand it over - Every attributed finding was read, not inferred from a title or snippet. - Every paper linked by DOI or arXiv id; preprints marked as such. - The window and priority stated; excluded well-known work explained by the window. - Coverage claims are modest: "no paper found in these sources under this window" rather than "no work exists".