mcpField

Skills

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

Data & databases

E
experience-lds-best-practices-apply
experience-lds-best-practices-apply
forcedotcom / sf-skills

Use when reviewing or implementing Lightning Data Service best practices in an LWC (.js, .html, .js-meta.xml) — UIAPI vs Apex, refreshApex / notifyRecordUpdateAvailable, @salesforce/schema imports, LDS record-form data patterns. TRIGGER on "apply LDS best practices to this LWC", "review this LWC for LDS best-practice issues", "review this component for Lightning Data Service issues", "UIAPI or Apex for this data?", "fix stale data after record save", "sync LDS cache", "use @salesforce/schema for field names", "choose between getRecord and Apex". DO NOT TRIGGER when building a new LWC (use experience-lwc-generate), applying SLDS design tokens (use design-systems-slds-apply), picking or wiring a `lightning-*` base component's props/events/slots generically (use experience-lwc-base-components-integrate — this skill covers only the LDS data-layer rationale, even when the fix involves a base record form), or for security / RTL / accessibility reviews (separate passes).

Development2.0k
G
geopandas
geopandas
k-dense-ai / scientific-agent-skills

Guidance and local audit tools for Python workflows that directly use GeoPandas GeoSeries, GeoDataFrame, spatial operations, or vector-data I/O

Data & databases2.0k
A
analytics-events
analytics-events
metabase / metabase

Add product analytics events to track user interactions in the Metabase frontend

Data & databases2.0k
S
stable-baselines3
stable-baselines3
k-dense-ai / scientific-agent-skills

Trains and evaluates single-agent reinforcement learning with Stable Baselines3 (PPO, SAC, DQN, TD3, DDPG, A2C), Gymnasium custom environments, vectorized rollouts, callbacks, and checkpoint normalization. Applies to reproducible RL experiments, continuous control, discrete actions, and SB3-Contrib recurrent or masked policies.

Data & databases2.0k
D
data-analysis
data-analysis
lingzhi227 / agent-research-skills

Generate statistical analysis code with 4-round review. Select appropriate statistical tests, interpret results, and produce analysis reports with p-values, effect sizes, and confidence intervals. Use when analyzing experimental data for a paper.

Data & databases2.0k
P
physical-ai-video-data-augmentation
physical-ai-video-data-augmentation
nvidia / skills

Use when running video data augmentation and auto-labeling workflows on OSMO: flow selection, preflight, submit-time interpolation, monitoring, and output retrieval. Trigger keywords: video data augmentation, data enrichment, auto labeling, VDA demo, OSMO workflow, pseudo labeling.

Data & databases2.0k
P
pymoo
pymoo
k-dense-ai / scientific-agent-skills

Solves and validates single-, multi-, and many-objective optimization with pymoo, including NSGA-II, NSGA-III, MOEA/D, constraints, Pareto approximations, reference directions, and ZDT/DTLZ benchmarks for engineering and research problems.

Data & databases2.0k
S
scikit-bio
scikit-bio
k-dense-ai / scientific-agent-skills

Biological data toolkit. Sequence analysis, alignments, phylogenetic trees, diversity metrics (alpha/beta, UniFrac), ordination (PCoA), PERMANOVA, FASTA/Newick I/O, for microbiome analysis.

Data & databases2.0k
C
ccf-experiment-designer
ccf-experiment-designer
mikubaka88 / ccfa-skills

Design and interpret CCF experiments: datasets, baselines, metrics, ablations, execution specifications, observed feedback, and result-table contents. Use for 设计实验, 消融, benchmark planning, 实验结果分析, and evidence design within requested autonomous research. Preserve real values. Orchestrator coordinates research-loop execution; visual styling and broad retrieval have separate owners

Data & databases2.0k
G
geomaster
geomaster
k-dense-ai / scientific-agent-skills

Supports geospatial research workflows for remote sensing, vector and raster GIS, spatial statistics, terrain and network analysis, and machine learning for Earth observation. Use when processing satellite imagery, aligning coordinate systems and raster grids, accessing STAC catalogs, analyzing geospatial time series, or implementing scientific GIS workflows in Python, R, Julia, JavaScript, C++, Java, Go, or Rust.

Data & databases2.0k
N
n8n-binary-and-data-official
n8n-binary-and-data-official
n8n-io / skills

Use when handling files, images, attachments, or binary data in n8n, OR when an AI agent needs to take a user-uploaded file as tool input or return a generated file. For Data Tables (schemas, dedup, persistent state), see the separate n8n-data-tables-official skill. Triggers on "file", "image", "PDF", "attachment", "binary", "upload", "download", chat trigger with files, agent tool that needs a file, vision/multimodal, or any handling of non-JSON file data.

Data & databases2.0k
S
simpy
simpy
k-dense-ai / scientific-agent-skills

Builds, inspects, tests, and analyzes bounded process-based discrete-event simulations with SimPy. Use for event scheduling, resource queues, interrupts, monitoring, independent replications, warm-up, and reproducible output analysis.

Data & databases2.0k
I
initiating-coverage
initiating-coverage
anthropics / financial-services

Create institutional-quality equity research initiation reports through a 5-task workflow. Tasks must be executed individually with verified prerequisites - (1) company research, (2) financial modeling, (3) valuation analysis, (4) chart generation, (5) final report assembly. Each task produces specific deliverables (markdown docs, Excel models, charts, or DOCX reports). Tasks 3-5 have dependencies on earlier tasks.

Data & databases2.0k
P
physical-ai-defect-image-generation
physical-ai-defect-image-generation
nvidia / skills

Use when the user wants to orchestrate defect image generation with NVIDIA Cosmos AnomalyGen (Cosmos-Predict2-derived) on OSMO for PCBA, metal surface, and glass inspection. The Day 0 path handles cold-start with USD-to-ROI, image-edit augmentation, and AnomalyGen to create initial PCBA datasets. The Day 1 path performs inference and labeling on real images. This skill helps with first-time asset setup, creation of finetuning checkpoints, and configuring deployment. Trigger keywords: defect image generation, dig workflow, dig pipeline, defect image detection workflow, aoi pipeline, aoi anomalygen, usd2roi anomalygen, day 0 pcba, day 1 pcba, day 1 real-photo alignment, day 1 manual roi, metal surface anomaly, glass defect, anomalygen finetune, setup_pcb, setup_metal, setup_glass, setup_pretrained, dig setup, dig datasets, dig pretrained checkpoint, dig image-edit endpoint, cosmos defect generation, cosmos-predict2 defect, cosmos-anomalygen, cosmos predict2 finetune.

Data & databases2.0k
H
hypogenic
hypogenic
k-dense-ai / scientific-agent-skills

Plans and audits use of ChicagoHAI HypoGeniC/HypoRefine for LLM-assisted hypothesis generation from labeled text datasets. Use for the `hypogenic` package, its task configs, hypothesis banks, or HypoBench datasets—not for manual hypothesis formulation or scientific validation.

Data & databases2.0k
N
n8n-binary-and-data
n8n-binary-and-data
czlonkowski / n8n-skills

Handle files and binary data in n8n correctly. Use when working with files, images, PDFs, attachments, uploads or downloads, base64, vision/multimodal input, or when an AI agent needs a file as tool input or output — and whenever the user mentions $binary, binaryPropertyName, "read the PDF", "attach the file", "send the image", Merge losing binary, or a CDN for chat images. Covers the $binary vs $json split, reading/writing binary, keeping binary alive across transforms with Merge, the agent-tool binary boundary, and the CDN/URL requirement for chat surfaces.

Data & databases2.0k
B
bioservices
bioservices
k-dense-ai / scientific-agent-skills

Provides a Python interface to bioinformatics services including UniProt, KEGG, ChEMBL, Reactome, QuickGO, and UniChem. Used for cross-database protein annotation, pathway retrieval, chemical identifier mapping, and integrated biological data workflows with BioServices

Data & databases2.0k
A
anndata
anndata
k-dense-ai / scientific-agent-skills

Handles annotated matrices in single-cell analysis, .h5ad and Zarr files, and integration with the scverse ecosystem. This is the data format skill—for analysis workflows use scanpy; for probabilistic models use scvi-tools; for population-scale queries use cellxgene-census

Data & databases2.0k
G
google-search-console
google-search-console
kostja94 / marketing-skills

Compatibility pointer for Search Console performance and indexing analysis; maintained in Open Analytics.

Marketing & growth2.0k
C
cms-migration
cms-migration
payloadcms / skills

Use when user wants to migrate content from another CMS (WordPress, Contentful, Strapi, Sanity, Webflow, etc.) to Payload CMS

Data & databases2.0k
C
clinical-decision-support
clinical-decision-support
k-dense-ai / scientific-agent-skills

Prepares and validates research-only clinical decision-support evaluation, evidence-profile, cohort, survival, biomarker/model, privacy, and governance artifacts. Supports aggregate or synthetic research documentation and traceability, excluding patient care and live clinical operation.

Documents2.0k
G
gget
gget
k-dense-ai / scientific-agent-skills

Queries 20+ bioinformatics resources through CLI/Python. Supports quick lookups of gene info, BLAST/BLAT, viral sequence downloads, PDB/mmCIF structures, G2P residue annotations, enrichment analysis, OpenTargets, COSMIC, CELLxGENE, and 8cube mouse specificity/expression data. Best for interactive exploration and simple queries. For batch processing or advanced BLAST use biopython; for multi-database Python workflows use bioservices.

Data & databases2.0k
H
huggingface-vision-trainer
huggingface-vision-trainer
huggingface / skills

Trains and fine-tunes vision models for object detection (D-FINE, RT-DETR v2, DETR, YOLOS), image classification (timm models — MobileNetV3, MobileViT, ResNet, ViT/DINOv3 — plus any Transformers classifier), and SAM/SAM2 segmentation using Hugging Face Transformers on Hugging Face Jobs cloud GPUs. Covers COCO-format dataset preparation, Albumentations augmentation, mAP/mAR evaluation, accuracy metrics, SAM segmentation with bbox/point prompts, DiceCE loss, hardware selection, cost estimation, Trackio monitoring, and Hub persistence. Use when users mention training object detection, image classification, SAM, SAM2, segmentation, image matting, DETR, D-FINE, RT-DETR, ViT, timm, MobileNet, ResNet, bounding box models, or fine-tuning vision models on Hugging Face Jobs.

Data & databases2.0k
R
rdkit
rdkit
k-dense-ai / scientific-agent-skills

Cheminformatics toolkit for fine-grained molecular control. SMILES/SDF parsing, descriptors (MW, LogP, TPSA), fingerprints, substructure search, 2D/3D generation, similarity, reactions. For standard workflows with simpler interface, use datamol (wrapper around RDKit). Use rdkit for advanced control, custom sanitization, specialized algorithms.

Data & databases2.0k
A
astropy
astropy
k-dense-ai / scientific-agent-skills

Core Python library for astronomy and astrophysics workflows that need Astropy APIs, including units/quantities, coordinates, FITS I/O, tables, time systems, WCS, and cosmology. Use when implementing or debugging astronomical data analysis code with Astropy.

Data & databases2.0k
S
scanpy
scanpy
k-dense-ai / scientific-agent-skills

Performs Scanpy single-cell RNA-seq QC, normalization, HVG selection, PCA/UMAP/t-SNE, clustering, exploratory marker ranking, pseudobulk preparation, visualization, and Seurat or SingleCellExperiment RDS conversion to h5ad. Applies to established exploratory scRNA-seq workflows with explicit count and expression provenance; complementary skills cover scvi-tools models and AnnData format details.

Data & databases2.0k
1
1start-mathmodel
1start-mathmodel
jihe520 / mathmodelagent

Entry point for the mathematical modeling competition workflow. Use to start the full modeling process: ask the user’s preferences, generate plan.md and todo.md, then call skills for each phase, including problem analysis, modeling, code and charts, flowcharts, paper writing, and validation and acceptance

Data & databases2.0k
C
cellxgene-census
cellxgene-census
k-dense-ai / scientific-agent-skills

Queries the CZ CELLxGENE Census programmatically for versioned public single-cell and spatial transcriptomics data. Use when you need population-scale cell metadata, gene expression slices, Census summary counts, source H5AD URIs/downloads, embeddings, spatial Census data, or reference atlas comparisons across organisms, tissues, diseases, assays, and cell types. For analyzing your own local single-cell data use scanpy, anndata, or scvi-tools.

Data & databases1.9k
P
pydicom
pydicom
k-dense-ai / scientific-agent-skills

Reads, inspects, writes, transforms, and preflights local DICOM datasets and pixel data. Applies to DICOM metadata, transfer syntaxes, compression plugins, frames, private elements, JSON, and bounded de-identification review.

Data & databases1.9k
D
deepchem
deepchem
k-dense-ai / scientific-agent-skills

Builds molecular property prediction and MoleculeNet workflows with DeepChem, including SMILES featurization, scaffold or grouped holdouts, masked labels, graph models and explicit pretrained encoder transfer. Used for ADMET, toxicity, solubility and chemistry ML when DeepChem data/model contracts and scientific validation are needed.

Data & databases1.9k
D
deeptools
deeptools
k-dense-ai / scientific-agent-skills

NGS analysis toolkit. BAM to bigWig conversion, QC (correlation, PCA, fingerprints), heatmaps/profiles (TSS, peaks), for ChIP-seq, RNA-seq, ATAC-seq visualization.

Data & databases1.9k
P
pufferlib
pufferlib
k-dense-ai / scientific-agent-skills

Version-aware guidance for PufferLib reinforcement-learning environments, vectorization, policies, PuffeRL training, evaluation, and safe checkpoint review. Covers the native 5.0 build and environment API, published 3.0.0 Gymnasium/PettingZoo adaptation, and a pinned historical 4.0 profile.

Development1.9k
D
datamol
datamol
k-dense-ai / scientific-agent-skills

Pythonic wrapper around RDKit with simplified interface and sensible defaults. Preferred for standard drug discovery including SMILES parsing, standardization, descriptors, fingerprints, clustering, 3D conformers, parallel processing. Returns native rdkit.Chem.Mol objects. For advanced control or custom parameters, use rdkit directly.

Data & databases1.9k
F
finlab
finlab
koreal6803 / finlab-ai

Comprehensive guide for FinLab quantitative trading package across global stock markets (TW, US, KR, JP, HK; both single-name equities and ETFs/funds). Use when working with trading strategies, backtesting, stock data, FinLabDataFrame, factor analysis, stock selection, or when the user mentions FinLab, trading, quant trading, US equity, S&P 500 / NASDAQ 100, SPY / QQQ, sector or leveraged ETFs, ETF rotation, 美股, or stock market analysis. Includes data access, strategy development, backtesting workflows, best practices, and US-market specifics (data availability map, filing-date-aligned quarterly fundamentals, US universe construction, USMarket vs. USFundMarket defaults, and ETF backtesting)

Data & databases1.9k
B
benchling-integration
benchling-integration
k-dense-ai / scientific-agent-skills

Benchling Python SDK and REST API integration for registry entities, inventory, ELN entries, workflows, Benchling Apps, and Data Warehouse queries. Use when automating lab data with benchling-sdk or the v2 API.

Data & databases1.9k
V
vaex
vaex
k-dense-ai / scientific-agent-skills

Processes large tabular scientific datasets with Vaex expressions, filtered views, streamed statistics, binned visualizations, and file conversion. Use for larger-than-RAM HDF5, Arrow, CSV, or Parquet analysis, virtual feature engineering, or Vaex ML preprocessing; distinguishes these operations from estimators and conversions that materialize data.

Data & databases1.9k
2
2analysis-modeling
2analysis-modeling
jihe520 / mathmodelagent

Combined stage for mathematical modeling contest problem analysis and model design. Use to read problem statements and attachments, break down subproblems, understand data, pre-check assumptions, define variables, formulate models and objective functions and constraints, plan solution strategies, and produce modeling reports ready for code implementation.

Data & databases1.9k
A
arboreto
arboreto
k-dense-ai / scientific-agent-skills

Infers candidate gene regulatory networks from bulk or single-cell expression data using AertsLab Arboreto GRNBoost2 and GENIE3. Use for transcription factor-target association ranking, compatible Dask execution, sparse expression inputs, and network stability checks.

Data & databases1.9k
M
molecular-dynamics
molecular-dynamics
k-dense-ai / scientific-agent-skills

Runs and analyzes molecular dynamics simulations with OpenMM and MDAnalysis. Sets up protein/small molecule systems, defines force fields, runs energy minimization and production MD, and analyzes trajectories (RMSD, RMSF, contact maps, free energy surfaces). For structural biology, drug binding, and biophysics.

Data & databases1.9k
P
pydeseq2
pydeseq2
k-dense-ai / scientific-agent-skills

Performs bulk RNA-seq differential expression analysis with PyDESeq2, including count validation, formula designs, explicit contrasts, Wald tests, FDR correction, coefficient-matched LFC shrinkage, and result visualization. Use for PyDESeq2 or Python DESeq2 workflows with biological replicates.

Data & databases1.9k
N
n8n-loops-official
n8n-loops-official
n8n-io / skills

Use when working with multi-item data, batches, paginated APIs, rate-limited APIs, fan-out across multiple branches, anything that needs to "do this for each", or any time the user mentions looping, iterating, batching, paging, parallelism, or "loop over items". Triggers on "loop", "iterate", "for each", "batch", "page through", "paginate", "rate limit", "process all", "fan-out", "parallel branches", "concurrency", or any node that should run once vs once-per-item.

Development1.9k
P
pymatgen
pymatgen
k-dense-ai / scientific-agent-skills

Analyzes, validates, converts, and transforms materials structures and computed materials data with pymatgen. Use for local phase diagrams, symmetry sensitivity, electronic-structure I/O, and bounded Materials Project queries.

Data & databases1.9k
T
torchdrug
torchdrug
k-dense-ai / scientific-agent-skills

Builds and troubleshoots TorchDrug 0.2.1 workflows for molecular graphs, property prediction, self-supervised pretraining, molecule generation, retrosynthesis, protein representation learning, and knowledge graph reasoning. Use when code imports torchdrug or needs its datasets, models, tasks, or Engine.

Data & databases1.9k
I
imaging-data-commons
imaging-data-commons
k-dense-ai / scientific-agent-skills

Queries and downloads public cancer imaging data from NCI Imaging Data Commons. Supports IDC collection discovery, DICOM access, radiology (CT, MR, PET) and pathology AI datasets, metadata SQL, visualization, licensing, and citations. Uses public metadata and download routes without authentication; optional BigQuery and Google Healthcare routes require Google credentials.

Data & databases1.9k
L
logfire-query
logfire-query
pydantic / skills

Query and analyze Logfire telemetry data — traces, logs, spans, metrics, summaries, and SQL results. Use this skill when the user asks to "query logfire", "search traces", "find logs", "query data", "search spans", "look up errors in logfire", "get metrics from logfire", "analyze telemetry", "summarize errors", "find root cause", or add Logfire querying capabilities to code. Do not use this skill for direct Logfire UI, browser, live-view, Explore-page, or link-opening requests; use logfire-ui instead. If "show" or "view" wording is ambiguous, ask whether the user wants a UI view or query analysis.

Data & databases1.9k
E
esm
esm
k-dense-ai / scientific-agent-skills

Uses the Biohub esm Python SDK for ESM3 protein generation, ESMC embeddings, and ESMFold2 all-atom folding. Applies to local model inference and Biohub hosted clients, including former Forge workflows; distinguishes the separate legacy fair-esm distribution.

Data & databases1.9k
Z
zarr-python
zarr-python
k-dense-ai / scientific-agent-skills

Stores and queries chunked N-D scientific arrays with Zarr-Python 3, including codecs, sharding, S3/GCS storage, and NumPy/Dask/Xarray integration. Use for array layout, bounded I/O, format migration, or scientific metadata preservation.

Data & databases1.9k
P
pyhealth
pyhealth
k-dense-ai / scientific-agent-skills

Builds and validates PyHealth clinical machine-learning pipelines for EHR, signals, imaging, and medical codes. Use for PyHealth dataset loading, MIMIC-III/IV, eICU or OMOP prediction tasks, patient-level evaluation, mortality/readmission/length-of-stay modeling, medication recommendation, sleep staging, Trainer checkpoints, and ICD/ATC/NDC/RxNorm mapping.

Data & databases1.9k
S
scvi-tools
scvi-tools
k-dense-ai / scientific-agent-skills

Fits probabilistic models for single-cell omics, including scVI batch integration, scANVI annotation, totalVI CITE-seq, MultiVI RNA/ATAC integration, and posterior differential expression. Use for generative modeling, reference mapping, multimodal analysis, or model-based uncertainty; use scanpy for standard preprocessing and exploratory analysis.

Data & databases1.9k
N
neurokit2
neurokit2
k-dense-ai / scientific-agent-skills

Builds and audits reproducible NeuroKit2 research workflows for physiological time-series preprocessing, event/interval analysis, multimodal alignment, variability, and complexity. Use when code imports neurokit2 or needs its current APIs, schemas, and method-aware validation—not for diagnosis or device validation.

Data & databases1.9k
M
medchem
medchem
k-dense-ai / scientific-agent-skills

Applies medicinal chemistry filters for compound triage, using drug-likeness rules (Lipinski, Veber, CNS), structural alert catalogs (PAINS, NIBR, ChEMBL), complexity metrics, and the medchem query language for library filtering.

Data & databases1.9k
D
depmap
depmap
k-dense-ai / scientific-agent-skills

Retrieves and analyzes Cancer Dependency Map (DepMap) release data, including CRISPR Chronos gene effects, cancer model annotations, omics biomarkers, and PRISM drug sensitivity. Supports cancer-selective dependency, co-essentiality, and candidate synthetic-lethality analyses with release-aware identifiers and statistical checks.

Data & databases1.9k
P
pysam
pysam
k-dense-ai / scientific-agent-skills

Provides Python/HTSlib workflows for genomic files. Used when reading, querying, filtering, or writing SAM/BAM/CRAM, VCF/BCF, FASTA/FASTQ, or tabix data with pysam, including pileup, coverage, indexing, and CRAM references.

Data & databases1.9k
C
cobrapy
cobrapy
k-dense-ai / scientific-agent-skills

Performs constraint-based metabolic modeling with COBRApy, including FBA, pFBA, FVA, gene knockouts, flux sampling, growth media, production envelopes, gap filling, and SBML model validation for systems biology and metabolic engineering.

Data & databases1.9k
D
diffdock
diffdock
k-dense-ai / scientific-agent-skills

Predicts protein-small-molecule binding poses with DiffDock and DiffDock-L from PDB or sequence plus SMILES/SDF/MOL2. Covers batch docking, pose triage, confidence interpretation, and validation. Use for molecular docking and virtual-screening pose generation, not binding-affinity prediction.

Data & databases1.9k
M
molfeat
molfeat
k-dense-ai / scientific-agent-skills

Featurizes small molecules with Molfeat for QSAR/QSPR, chemical similarity, virtual screening, and molecular ML. Covers ECFP/MACCS fingerprints, RDKit descriptors, pharmacophores, pretrained embeddings, configuration persistence, and molecule-to-label alignment.

Data & databases1.9k
N
n8n-data-tables-official
n8n-data-tables-official
n8n-io / skills

Use when working with n8n's built-in Data Tables, designing schemas, inserting/updating/upserting rows, deduping, or querying. Triggers on "Data Table", "data table", `n8n-nodes-base.dataTable`, "dedup", "idempotency", "lookup", "persistent state", "store across executions", or any schema design discussion inside n8n.

Data & databases1.9k
P
pathml
pathml
k-dense-ai / scientific-agent-skills

Supports local computational pathology research with PathML: slide loading and tiling, preprocessing and QC, h5path storage, multiplex quantification, spatial graphs, and bounded model inference. Use for whole-slide H&E, CODEX, Vectra, Mesmer, HoVer-Net, and HACTNet workflows.

Data & databases1.9k
P
pennylane
pennylane
k-dense-ai / scientific-agent-skills

Builds and differentiates PennyLane quantum circuits, hybrid PyTorch or JAX models, molecular VQE and QAOA workflows. Use for variational quantum algorithms, quantum machine learning, simulator validation, and moving validated circuits to provider plugins. For hardware-specific compilation use qiskit or cirq; for open-system dynamics use qutip.

Development1.9k
E
etetoolkit
etetoolkit
k-dense-ai / scientific-agent-skills

Analyzes, manipulates, compares, annotates, and visualizes phylogenetic or other hierarchical trees with ETE 4. Supports Newick/Nexus tree I/O, topology edits and pattern matching, Robinson-Foulds comparisons, gene-tree evolutionary events and reconciliation, NCBI/GTDB taxonomy, SmartView exploration, and publication rendering. Applies to existing trees after alignment and phylogenetic inference, rather than inferring trees from raw sequences.

Data & databases1.9k
1021–1080 of 12,302

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.