mcpField

Skills

96,981 packaged capabilities and playbooks for agents. Install any of them with one command.

Documents

E
efficient-literature-survey
efficient-literature-survey
namooubn / efficient-literature-survey

Use when the user needs to batch-read academic literature (10+ files) and write a thesis introduction or literature review. Triggers on phrases like "帮我读文献", "literature review", "batch read papers", or when the user has a folder of literature files needing structured academic output.

Productivity125
G
GordenImage2PPTX
GordenImage2PPTX
gordensun / gordensuperpptskills

Reverse-engineer an image-format PPT document, slide screenshot, or any image page into an editable .pptx. The four-layer process is mandatory: replicate the background image + cut out the overall skeleton with a green screen + cut out element icons/decorations with a green screen + extract text with GPT vision, then composite (text becomes real text boxes, skeleton and icons become movable images; only split the skeleton into parts when the user explicitly asks for it). Converts slide images back into an editable PPTX via background + skeleton + icons + text layers. Use when the user wants to "convert PPT images/screenshots to editable PPTX, restore image PPTs to editable PPT, cut out icons, replicate backgrounds, extract text, restore layout". Input is an image, output is an editable .pptx.

Documents125
M
make-resume
make-resume
hisn00w / asu-skills

Editable Chinese resume creation skill: by default it uses the ASu single-column high-density technical resume template and creates or reproduces an editable HTML/PDF from the user's experience; the user may also specify other templates in the repository, local HTML, or a reference screenshot. Use when the user enters "/make-resume", "我要阿酥同款简历", or asks to create, modify, or reproduce a resume file; when the user requests a LaTeX, `.tex`, or Overleaf version, additionally export a `.tex` source file alongside the default HTML deliverable.

Documents125
P
persian-writing
persian-writing
ali2000hos / persian-writing

Write natural, human-sounding Persian (Farsi) and build correct right-to-left Persian deliverables. Use for ANY task involving Persian text or an Iranian audience: writing, editing, translating, humanizing, SEO content and copywriting (سئو، کپی‌رایتینگ، لندینگ), academic papers/theses, and Persian output in Word/.docx, PDF, PowerPoint, HTML, Excel, images/posters, emails, social posts. Covers register detection (رسمی/اداری/محاوره/علمی — errors here are costly), Persian AI-tell removal, orthography (نیم‌فاصله/ZWNJ، اعداد فارسی، «گیومه»), cleanup and spell-check (ویرایش، پاکسازی — bundled paknevis+davat toolkit), RTL layout/pagination fixes, and Persian fonts (Vazirmatn bundled). Trigger whenever you see Persian/Arabic script or words like فارسی, Farsi, Persian, Iran, RTL, راست‌چین, نیم‌فاصله, ویرایش, مقاله, پایان‌نامه, سئو, کپشن, Vazirmatn — even if the user never mentions this skill.

Creative & media125
P
present-paper
present-paper
aperivue / medsci-skills

Use when preparing an academic talk such as a journal club, grand rounds, seminar, conference presentation, or lecture/teaching deck. Analyzes the source, drafts audience-adapted speaker scripts, builds or augments the PPTX with speaker notes and prepares Q&A.

Documents125
P
preview
preview
companion-inc / feynman

Render Markdown or LaTeX research artifacts to HTML or PDF with pandoc. Use when the user wants to review a written artifact, export a report, or view a rendered document.

Documents125
P
puppeteer
puppeteer
aidotnet / moyucode

Browser automation and PDF generation with Puppeteer (Google). Supports headless Chrome control for web scraping, screenshots, PDF generation and automated testing.

Development125
S
self-review
self-review
aperivue / medsci-skills

Use when checking your own manuscript before submission from a reviewer's perspective. Returns anticipated Major/Minor comments with fixes, including numerical, citation and leakage checks, with an optional multi-reviewer panel. Someone else's paper is /peer-review.

Documents125
S
summarize
summarize
nkchivas / openclaw-skill-summarize

Summarize or extract text/transcripts from URLs, podcasts, and local files (great fallback for "transcribe this YouTube/video").

Productivity125
S
swain-design
swain-design
cristoslc / swain

Create, validate, and transition documentation artifacts (Vision, Initiative, Epic, Spec, Spike, ADR, Persona, Runbook, Design, Journey) through lifecycle phases. Handles spec writing, feature planning, epic creation, initiative creation, ADR drafting, research spikes, persona definition, runbook creation, design capture, architecture docs, phase transitions, implementation planning, cross-reference validation, and audits. Also invoke to update frontmatter fields, re-parent an artifact under a different epic or initiative, or set priority on a Vision or Initiative. Chains into swain-do for implementation tracking on SPEC; decomposes EPIC/VISION/INITIATIVE/JOURNEY into children first.

Development125
V
verify-citations
verify-citations
shaishavmaisuria / research-paper-lifecycle-skills

Verifies every citation in a BibTeX .bib file against Crossref, DBLP, Semantic Scholar, and arXiv to catch hallucinated, fabricated, or incorrect references before reviewers do. Use when the user says verify citations, check references, validate bibliography, check my .bib, fake or hallucinated citations, retracted paper, or DOI check — and before any draft, rebuttal, or camera-ready leaves the machine. Flags unresolvable entries (likely fabrications), author/year/venue mismatches, duplicates, and retractions, and points to the canonical record for each fix. Every skill that writes or edits citations must route new references through this gate.

Documents125
A
aigc-down-skill
aigc-down-skill
yezery / aigc-down-skill

A specialized skill for lowering the AIGC detection rate in Chinese academic writing (undergraduate/college graduation theses). Based on patterns summarized from real thesis rewriting experiments (AIGC rate reduced from >50% to 11%), and referencing Wikipedia's 'Signs of AI writing' systematic pattern classification. Detects and fixes typical patterns in Chinese AI writing, including: theory-justification openings, "this case confirms" formulaic endings, neat parallel clauses, templated problem statements, passive analytical filler, overly symmetrical structures, superfluous summary sentences, vague attributions, filler phrases, generic positive conclusions, and the overuse of high-frequency AI vocabulary. Use when the user asks to: lower AI rate, humanize, reduce AIGC, humanize, remove AI flavor, polish academic writing, reduce thesis repetition, AIGC detection, remove AI traces, lower a thesis's AI rate, remove AI writing traces, humanize academic text, AIGC detection report.

Documents124
E
equity-researcher
equity-researcher
lzwme / finance-quant-skills

Institutional-grade equity research report generation skill. Covers listed companies on China A-shares, Hong Kong stocks, and US stocks. Output modes: 1) Investment snapshot: 3-5 pages, including company overview, core financial metrics, valuation multiples, investment thesis, and risk factors; 2) In-depth research report: ≥25 pages, including industry analysis, industry chain mapping, three-statement model, DCF valuation, scenario analysis, and sensitivity testing. Trigger conditions: 1) Direct requests: analyze/look at/research/investigate/introduce + company name or stock; 2) Investment inquiries: what do you think/can I buy/is it worth investing/help me look/dig into + company or stock; 3) Keywords: research report, investment brief, investment snapshot, company one-pager, in-depth research report, in-depth research, in-depth analysis, individual stock analysis, one-pager, snapshot, company snapshot, equity research report; 4) Stock tickers: standard formats (e.g. 600519.SH, 0700.HK, AAPL, TSLA, BYD). When the intent is unclear, proactively ask for the output mode; never infer by default.

Data & databases124
F
feishu-cli-meetings
feishu-cli-meetings
riba2534 / feishu-cli

Query Feishu historical video meetings, minutes, AI summaries, transcripts and recordings, read or download Minutes by minute token, and operate the meeting bot to join/leave meetings and query meeting events. For creating schedules, finding shared free time and booking meeting rooms, use feishu-cli-work.

Productivity124
K
karpathy-output-evolution
karpathy-output-evolution
learnprompt / andrej-karpathy-skills

Upgrade LLM outputs from plain text to structured, rendered formats like HTML, Marp slides, or interactive dashboards. Use this skill when the user wants better-formatted output, needs to convert notes into a presentation, wants HTML output from an LLM, needs slides from a document, or says "make this prettier", "render this", "output as HTML", "make slides from this", "structured output", "Marp", "better format". Based on Karpathy 19k-like HTML output post.

Documents124
P
paper-details
paper-details
mathbullet / skills

Produce a detailed Markdown explainer of an academic paper. The skill aims for faithful description, not critical review. Section structure mirrors the original paper, equations render as LaTeX with variable tables, citations to the paper under review use position only, and citations to other works use author-short form. Use when the user asks for a detailed paper write-up, a thorough paper explainer, or invokes "paper details". Depends on documenting-with-sources and writing-quotation.

Documents124
P
phrase
phrase
membranedev / application-skills

Phrase integration. Manage Organizations. Use when the user wants to interact with Phrase data.

Development124
P
pptx

No description yet

Documents124
S
slides
slides
letta-ai / skills

Create and edit presentation slide decks (`.pptx`) with PptxGenJS, bundled layout helpers, and render/validation utilities. Use when tasks involve building a new PowerPoint deck, recreating slides from screenshots/PDFs/reference decks, modifying slide content while preserving editable output, adding charts/diagrams/visuals, or diagnosing layout issues such as overflow, overlaps, and font substitution.

Documents124
T
themes
themes
igorwarzocha / opencode-workflows

Apply professional visual themes to documents and presentations. Use for styling artifacts with consistent color palettes and font pairings. Use proactively to quickly improve the aesthetic quality of deliverables. Examples: - user: "Apply a modern theme to this deck" -> use Modern Minimalist theme - user: "I want a tech aesthetic for this doc" -> apply Tech Innovation theme - user: "Create a custom theme for my project" -> generate new color/font specification

Design & UI124
T
typst-writer
typst-writer
ypares / agent-skills

Write correct and idiomatic Typst code for document typesetting. Use when creating or editing Typst (.typ) files, working with Typst markup, or answering questions about Typst syntax and features. Focuses on avoiding common syntax confusion (arrays vs content blocks, proper function definitions, state management).

Documents124
A
academic-letter-architect
academic-letter-architect
lyndonkl / claude

Guides the creation of evidence-based academic recommendation letters, reference letters, and award nominations that combine concrete examples, meaningful comparisons, and genuine enthusiasm. Use when writing recommendation letters for students, postdocs, or colleagues, or when user mentions recommendation letter, reference, nomination, letter of support, endorsement, or needs help with strong advocacy and comparative statements.

Documents123
C
consulting-pptx-skill
consulting-pptx-skill
carnot-tech / jinba-consulting-pptx-skill

A skill for creating executive-meeting-quality slides, built around the slide design rules in slide-rules.md. Retrieve only the sections needed for each stage with scripts/rules.py, assemble from components verified against the rules (20 types listed by new_deck.py --list), and finish with zero mechanical-check FAILs from check_deck.py and check_layout.mjs. Only when given an existing PowerPoint and asked for pages to insert into it as PPTX, build directly on that document’s master (slide-rules §8.7). Trigger examples: “Create consulting-quality slides,” “Make a deck that follows the rules,” “Add pages to this pptx in the same format.”

Documents123
F
frappe-syntax-jinja
frappe-syntax-jinja
impertio-studio / frappe_claude_skill_package

Use when writing Jinja templates for ERPNext/Frappe Print Formats, Email Templates, and Portal Pages. Covers template syntax, context variables, filters, macros, and v16 Chrome PDF rendering. Prevents common mistakes with doc context and child table iteration. Keywords: Jinja, print format, email template, portal page, template syntax, PDF, v14-v16, template syntax, Jinja example, print format code, how to show child table in print.

Development123
F
fulltext-retrieval
fulltext-retrieval
aperivue / medsci-skills

Use when you need full-text PDFs for a list of DOIs, such as a meta-analysis screening set. Batch-downloads open-access copies via Unpaywall, PMC, OpenAlex and Crossref, lists paywalled papers for manual access, and can convert PDFs to Markdown.

Documents123
G
generate-writeup
generate-writeup
pamelafox / presentation-skills

Generate an annotated blog-style write-up from a presentation's slides and video recording. Orchestrates the full pipeline: fetching slides, converting to images, extracting transcript, generating chapters, outlining slides, and producing the final annotated markdown. USE FOR: write-up, blog post, presentation summary, annotated write-up, generate writeup.

Documents123
H
human-facing-writing
human-facing-writing
porada / domfiles

Draft, edit, review, and refine all human-facing writing, from short-form copy to connected prose. Use whenever readers must follow ideas, context, reasoning, narrative, or tone. Apply across technical surfaces such as package and repository descriptions, README and technical document content or information architecture, CLI wording, JSDoc and docstrings, explanatory source comments, runtime messages, test titles, labels, and issue, pull request, and discussion copy. Don’t use for LICENSE text, formatting-only work, or tasks that neither evaluate nor change wording or information architecture. Agent responses alone aren’t a trigger.

Documents123
H
hwpx
hwpx
canine89 / gonggong_hwpxskills

A skill for creating, reading, editing, and template-substituting HWPX documents (.hwpx files). When keywords such as '한글 문서', 'hwpx', 'HWPX', '한글파일', '.hwpx 파일 만들어줘', 'HWP 문서 생성', '보고서', '공문', '기안문', '한글로 작성' appear, you must use this skill. It handles HWPX format (based on KS X 6101/OWPML, ZIP+XML structure) from Hancom with the python-hwpx library. If you need a report template, use the reference templates in the assets/ folder. For ordinary Word (.docx) documents, use the docx skill.

Documents123
I
integration-create
integration-create
google / adk-docs

Creates a new ADK integration documentation page (a Markdown file under docs/integrations/) for a third-party tool, plugin, observability platform, data store, MCP server, or connector. Gathers details, picks the right category template, and drafts a page that follows adk-docs conventions. Triggers on "integration-create", "create integration page", "new integration", "add an integration", "write an integration page".

Development123
K
k12-lesson-plan-creation
k12-lesson-plan-creation
anthropics / k12-teacher-skills

Creates a lesson plan, student-facing materials, and observation template. Load this skill BEFORE asking the teacher any clarifying question about grade, subject, topic, standard, or timing. Use when a K-12 teacher needs a math, ELA, science, or social studies lesson built from scratch — even if grade, subject, or topic isn't yet stated. Do NOT load for grading, a rubric, assessment feedback, a quiz, or a standards lookup — answer those directly. Triggers on explicit requests (lesson plan, mini-lesson, unit plan, daily plan) and implicit teacher intent: "I'm teaching long division to 5th graders," "need to teach photosynthesis tomorrow." Core signal: teacher needs new instructional content created. A new lesson that asks for differentiated, tiered, or leveled materials is still ONE planning request — this skill produces those materials inside the lesson package; do not also invoke k12-lesson-differentiation. Not for differentiating an existing lesson (use k12-lesson-differentiation) or passage rewrites.

Documents123
M
monthly-invoice-summary
monthly-invoice-summary
steveclarke / dotfiles

Generate client-friendly monthly invoice summaries from Git commits and timesheet notes. Use when preparing monthly billing or project status reports.

Documents123
N
niw-petition
niw-petition
tapntell-ai / openniw

Prepares a complete EB-2 NIW (National Interest Waiver) self-petition package in a local case folder — free evaluation from a Google Scholar profile or CV, evidence checklist and citation pipeline, drafting the Proposed Endeavor Statement, Petition Letter and support letters in the structure of real approved filings, filling official USCIS/DOL PDFs, assembling the filing package, and running a deadline-driven response if USCIS issues an RFE. Use when the user mentions NIW, EB-2, national interest waiver, I-140 self-petition, RFE response, Request for Evidence, NOID, 国家利益豁免, 补件, 补充材料通知, or preparing a U.S. green-card petition from their research record. Document preparation only, not legal advice.

Documents123
P
pdf-convert-to-word
pdf-convert-to-word
stvlynn / dingtalk-wukong-skills

Convert PDF files into editable Word and Markdown outputs with the bundled conversion scripts and workflow guide.

Documents123
P
pdf-process-mineru

PDF document parsing tool based on local MinerU, supports converting PDF to Markdown, JSON, and other machine-readable formats.

Documents123
P
pdf
pdf
stvlynn / dingtalk-wukong-skills

Comprehensive PDF manipulation toolkit for extracting text and tables, creating new PDFs, merging/splitting documents, and handling forms. When Claude needs to fill in a PDF form or programmatically process, generate, or analyze PDF documents at scale.

Documents123
P
pptx
pptx
aaaaqwq / agi-super-team

Presentation creation, editing, and analysis. When Claude needs to work with presentations (.pptx files) for: (1) Creating new presentations, (2) Modifying or editing content, (3) Working with layouts, (4) Adding comments or speaker notes, or any other presentation tasks

Documents123
P
psigen-software
psigen-software
membranedev / application-skills

PSIGEN Software integration. Manage data, records, and automate workflows. Use when the user wants to interact with PSIGEN Software data.

Documents123
A
academic-citation-manager
academic-citation-manager
youstudyeveryday / academic-citation-manager

Add real references and standardize citation markup for research papers and theses

Documents122
A
arabic-presentations
arabic-presentations
sultanalsafran / agent-skills

Create, edit, repair, and validate Arabic-first or Arabic-English PowerPoint decks with native editable PPTX text, paragraph-level RTL, correct mixed Arabic/Latin/number behavior, native bullets, Arabic language metadata, and PowerPoint-first QA. Use together with the Presentations skill whenever a deck contains Arabic, requires RTL or bilingual slides, must remain editable as .pptx, or renders Arabic differently in PowerPoint, Keynote, Google Slides, or Codex preview.

Documents122
D
daily-progress-report
daily-progress-report
datadrivenconstruction / ddc_skills_for_ai_agents_in_construction

Generate automated daily progress reports from site data. Track work completed, labor hours, equipment usage, and weather conditions.

Documents122
D
ddd-architecture-doc
ddd-architecture-doc
full-stack-skills / ddd-skills

DDD architecture documentation generation — C4 model diagrams (Context/Container/Component/Code), ADR (Architecture Decision Records), domain model documentation, API documentation, architecture decision log, and team communication templates. Use when user asks about architecture documentation, 架构文档, ADR, C4 diagram, domain model doc, 架构决策记录, or needs to document DDD architecture for team.

Development122
F
figma-slides
figma-slides
southleft / figma-console-mcp-skills

Author Figma Slides presentations — list/create/duplicate/reorder/delete slides, read the slide grid, add text and shapes to a slide, set slide background color, set or read slide transitions (dissolve, slide-from, push-from, smart-animate), focus a slide, and toggle skip. Use when the user wants to build or edit a Figma Slides deck. Triggers: 'create a slide', 'add a slide to the deck', 'reorder slides', 'set the slide background', 'add a transition between slides', 'add text/shape to slide 3', 'read what's on this slide', 'skip this slide in the presentation'. Figma Slides files only (figma.editorType === 'slides'). Requires the Figma Desktop app (Plugin API).

Documents122
G
googlesheets-automation
googlesheets-automation
davepoon / buildwithclaude

Automate Google Sheets operations (read, write, format, filter, manage spreadsheets) via Rube MCP (Composio). Read/write data, manage tabs, apply formatting, and search rows programmatically

Data & databases122
M
manage-refs
manage-refs
aperivue / medsci-skills

Use when references must be written, rendered or converted. Checks [@key] citation keys, renders the reference list with a journal CSL via pandoc, converts [N] markers, injects Zotero Word field codes and runs manuscript-DOCX cross-reference QC. Read-only auditing is /verify-refs.

Documents122
M
markdownlint
markdownlint
rshade / agent-skills

Validate markdown files against formatting standards. Auto-detects and installs markdownlint-cli if missing. Checks project config or falls back to sensible defaults. Supports auto-fix mode. Use when creating or modifying markdown files, validating documentation, or enforcing markdown conventions.

Testing & quality122
M
marketing-slides
marketing-slides
openclaudia / openclaudia-skills

Create marketing slides, pitch decks, sales decks, and product presentations. Use when the user says "create slides", "marketing slides", "pitch deck", "sales deck", "make a presentation", "slide deck", "product deck", "webinar slides", or wants any deck-shaped marketing asset.

Marketing & growth122
M
mck-ppt-design

Create professional, consultant-grade PowerPoint presentations from scratch using python-pptx with McKinsey-style design. Use when the user asks to create slides, pitch decks, business presentations, strategy decks, quarterly reviews, board meeting slides, or any professional PPTX. Generates clean, flat-design presentations with 36 layout patterns, consistent typography, and zero file-corruption issues.

Documents122
O
one-pager-prd
one-pager-prd
lyndonkl / claude

Creates concise, decision-ready product specifications (one-pagers and PRDs) that align stakeholders on problem, solution, users, success metrics, and constraints. Use when proposing new features/products, documenting product requirements, creating concise specs for stakeholder alignment, pitching initiatives, scoping projects before detailed design, capturing user stories and success metrics, or when user mentions one-pager, PRD, product spec, feature proposal, product requirements, or brief.

Documents122
P
pdf-to-images
pdf-to-images
crazynomad / skills

Convert PDF files into a series of images (PNG/JPG) using ImageMagick

Documents122
S
submission-audit
submission-audit
boom5426 / nature-paper-skills

Use when a manuscript is close to submission or resubmission and you need a preflight audit for claim support, figure-panel coverage, legend sync, methods references, terminology stability, and venue-facing risks.

Documents122
S
syncfusion-react-pdf-viewer
syncfusion-react-pdf-viewer
syncfusion / pdf-viewer-sdk-skills

Implements the Syncfusion React PDF Viewer (PdfViewerComponent) for embedding, configuring, and loading PDF documents. Use this when rendering PDFs in a React application, embedding viewer controls, or generating TSX/HTML code for PDF display and interaction.

Development122
T
table-extractor
table-extractor
dkyazzentwatwa / chatgpt-skills

Extract tables from PDFs and images to CSV or Excel. Support for scanned documents with OCR, multi-page PDFs, and complex table structures.

Documents122
T
transilience-report-style
transilience-report-style
transilienceai / communitytools

Generate a Transilience-branded PDF report (pentest, vuln assessment, compliance, threat intel) from a single findings JSON using the bundled ReportLab generator. Use whenever an engagement needs its final report/deliverable PDF in Transilience house style.

Documents122
W
writing-simplified-technical-english
writing-simplified-technical-english
posthog / ai-plugin

Write English that a reader cannot misread: one meaning per word, active voice, simple tenses, one idea per sentence, short sentences. Based on ASD-STE100 (Simplified Technical English), the controlled-language standard written for aircraft maintenance manuals. Use it for any prose an agent produces that someone else acts on. That covers reports and findings, PR descriptions and commit messages, instructions handed to another agent, tool descriptions, error messages, status summaries, and prompts. Also use it on request, with triggers like "simplify this", "make this readable", "too dense", "rewrite in STE", "simplified technical english", "ASD-STE100".

Documents122
B
BRD Creation
BRD Creation
danhvb / my-ba-skills

Guide AI assistants in creating professional Business Requirement Documents for Web, Mobile, ERP, CRM, CDP, and E-commerce projects

Documents121
C
comet-bilingual-docs
comet-bilingual-docs
rpamis / comet

Synchronize Comet's Chinese and English docs, README, Skills, release notes, and website pages while preserving confirmed semantics, repository structure, submodule boundaries, and focused validation. Use when documentation changes must stay bilingual, or when Chinese wording needs a corresponding English version.

Documents121
C
comet-release
comet-release
rpamis / comet

Prepare a Comet release or release notes update based on the real version and branch scope, keeping the changelog user-facing, the bilingual website docs consistent, generated assets validated, and the Git delivery boundary explicit. Use for beta, hotfix, version checks, release notes, or release readiness checks.

Development121
F
fund-research-content-writer
fund-research-content-writer
huiyuli-2000 / chinese-grant-writer-skills

NSFC research proposal writing assistant (research objectives, research content, key scientific questions). Triggered when the user needs to write the research content of a grant application, break down research topics, or distill scientific questions. Defaults to the General Program, and supports Key, Young Scientists, and provincial funds.

Documents121
M
mermaid-diagrams
mermaid-diagrams
sammcj / agentic-coding

Use the mermaid-diagrams skill whenever you are creating or updating mermaid diagrams. Provides guidance on mermaid best practices.

Design & UI121
M
mermaid
mermaid
partme-ai / full-stack-skills

Create Mermaid diagrams for Markdown documentation including flowcharts, sequence diagrams, class diagrams, state diagrams, ER diagrams, Gantt charts, pie charts, mindmaps, timelines, C4 diagrams, and 20+ other diagram types. Use when the user wants to draw, create, or visualize diagrams in Markdown-friendly format, mentions Mermaid, needs diagrams for GitHub/GitLab/wikis, or wants quick diagrams that render directly in Markdown renderers.

Documents121
2521–2580 of 5,929

New to MCP?

From what the protocol is to installing your first server, these answers cover most first questions.

An open protocol that defines how AI applications connect to external tools and data in a uniform way. Clients talk to the model; MCP servers provide tools, resources and prompt templates. They exchange standard messages, so one server can be reused by many clients.