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+---
+name: fluidsim
+description: Framework for computational fluid dynamics simulations using Python. Use when running fluid dynamics simulations including Navier-Stokes equations (2D/3D), shallow water equations, stratified flows, or when analyzing turbulence, vortex dynamics, or geophysical flows. Provides pseudospectral methods with FFT, HPC support, and comprehensive output analysis.
+---
+
+# FluidSim
+
+## Overview
+
+FluidSim is an object-oriented Python framework for high-performance computational fluid dynamics (CFD) simulations. It provides solvers for periodic-domain equations using pseudospectral methods with FFT, delivering performance comparable to Fortran/C++ while maintaining Python's ease of use.
+
+**Key strengths**:
+- Multiple solvers: 2D/3D Navier-Stokes, shallow water, stratified flows
+- High performance: Pythran/Transonic compilation, MPI parallelization
+- Complete workflow: Parameter configuration, simulation execution, output analysis
+- Interactive analysis: Python-based post-processing and visualization
+
+## Core Capabilities
+
+### 1. Installation and Setup
+
+Install fluidsim using uv with appropriate feature flags:
+
+```bash
+# Basic installation
+uv uv pip install fluidsim
+
+# With FFT support (required for most solvers)
+uv uv pip install "fluidsim[fft]"
+
+# With MPI for parallel computing
+uv uv pip install "fluidsim[fft,mpi]"
+```
+
+Set environment variables for output directories (optional):
+
+```bash
+export FLUIDSIM_PATH=/path/to/simulation/outputs
+export FLUIDDYN_PATH_SCRATCH=/path/to/working/directory
+```
+
+No API keys or authentication required.
+
+See `references/installation.md` for complete installation instructions and environment configuration.
+
+### 2. Running Simulations
+
+Standard workflow consists of five steps:
+
+**Step 1**: Import solver
+```python
+from fluidsim.solvers.ns2d.solver import Simul
+```
+
+**Step 2**: Create and configure parameters
+```python
+params = Simul.create_default_params()
+params.oper.nx = params.oper.ny = 256
+params.oper.Lx = params.oper.Ly = 2 * 3.14159
+params.nu_2 = 1e-3
+params.time_stepping.t_end = 10.0
+params.init_fields.type = "noise"
+```
+
+**Step 3**: Instantiate simulation
+```python
+sim = Simul(params)
+```
+
+**Step 4**: Execute
+```python
+sim.time_stepping.start()
+```
+
+**Step 5**: Analyze results
+```python
+sim.output.phys_fields.plot("vorticity")
+sim.output.spatial_means.plot()
+```
+
+See `references/simulation_workflow.md` for complete examples, restarting simulations, and cluster deployment.
+
+### 3. Available Solvers
+
+Choose solver based on physical problem:
+
+**2D Navier-Stokes** (`ns2d`): 2D turbulence, vortex dynamics
+```python
+from fluidsim.solvers.ns2d.solver import Simul
+```
+
+**3D Navier-Stokes** (`ns3d`): 3D turbulence, realistic flows
+```python
+from fluidsim.solvers.ns3d.solver import Simul
+```
+
+**Stratified flows** (`ns2d.strat`, `ns3d.strat`): Oceanic/atmospheric flows
+```python
+from fluidsim.solvers.ns2d.strat.solver import Simul
+params.N = 1.0  # Brunt-Väisälä frequency
+```
+
+**Shallow water** (`sw1l`): Geophysical flows, rotating systems
+```python
+from fluidsim.solvers.sw1l.solver import Simul
+params.f = 1.0  # Coriolis parameter
+```
+
+See `references/solvers.md` for complete solver list and selection guidance.
+
+### 4. Parameter Configuration
+
+Parameters are organized hierarchically and accessed via dot notation:
+
+**Domain and resolution**:
+```python
+params.oper.nx = 256  # grid points
+params.oper.Lx = 2 * pi  # domain size
+```
+
+**Physical parameters**:
+```python
+params.nu_2 = 1e-3  # viscosity
+params.nu_4 = 0     # hyperviscosity (optional)
+```
+
+**Time stepping**:
+```python
+params.time_stepping.t_end = 10.0
+params.time_stepping.USE_CFL = True  # adaptive time step
+params.time_stepping.CFL = 0.5
+```
+
+**Initial conditions**:
+```python
+params.init_fields.type = "noise"  # or "dipole", "vortex", "from_file", "in_script"
+```
+
+**Output settings**:
+```python
+params.output.periods_save.phys_fields = 1.0  # save every 1.0 time units
+params.output.periods_save.spectra = 0.5
+params.output.periods_save.spatial_means = 0.1
+```
+
+The Parameters object raises `AttributeError` for typos, preventing silent configuration errors.
+
+See `references/parameters.md` for comprehensive parameter documentation.
+
+### 5. Output and Analysis
+
+FluidSim produces multiple output types automatically saved during simulation:
+
+**Physical fields**: Velocity, vorticity in HDF5 format
+```python
+sim.output.phys_fields.plot("vorticity")
+sim.output.phys_fields.plot("vx")
+```
+
+**Spatial means**: Time series of volume-averaged quantities
+```python
+sim.output.spatial_means.plot()
+```
+
+**Spectra**: Energy and enstrophy spectra
+```python
+sim.output.spectra.plot1d()
+sim.output.spectra.plot2d()
+```
+
+**Load previous simulations**:
+```python
+from fluidsim import load_sim_for_plot
+sim = load_sim_for_plot("simulation_dir")
+sim.output.phys_fields.plot()
+```
+
+**Advanced visualization**: Open `.h5` files in ParaView or VisIt for 3D visualization.
+
+See `references/output_analysis.md` for detailed analysis workflows, parametric study analysis, and data export.
+
+### 6. Advanced Features
+
+**Custom forcing**: Maintain turbulence or drive specific dynamics
+```python
+params.forcing.enable = True
+params.forcing.type = "tcrandom"  # time-correlated random forcing
+params.forcing.forcing_rate = 1.0
+```
+
+**Custom initial conditions**: Define fields in script
+```python
+params.init_fields.type = "in_script"
+sim = Simul(params)
+X, Y = sim.oper.get_XY_loc()
+vx = sim.state.state_phys.get_var("vx")
+vx[:] = sin(X) * cos(Y)
+sim.time_stepping.start()
+```
+
+**MPI parallelization**: Run on multiple processors
+```bash
+mpirun -np 8 python simulation_script.py
+```
+
+**Parametric studies**: Run multiple simulations with different parameters
+```python
+for nu in [1e-3, 5e-4, 1e-4]:
+    params = Simul.create_default_params()
+    params.nu_2 = nu
+    params.output.sub_directory = f"nu{nu}"
+    sim = Simul(params)
+    sim.time_stepping.start()
+```
+
+See `references/advanced_features.md` for forcing types, custom solvers, cluster submission, and performance optimization.
+
+## Common Use Cases
+
+### 2D Turbulence Study
+
+```python
+from fluidsim.solvers.ns2d.solver import Simul
+from math import pi
+
+params = Simul.create_default_params()
+params.oper.nx = params.oper.ny = 512
+params.oper.Lx = params.oper.Ly = 2 * pi
+params.nu_2 = 1e-4
+params.time_stepping.t_end = 50.0
+params.time_stepping.USE_CFL = True
+params.init_fields.type = "noise"
+params.output.periods_save.phys_fields = 5.0
+params.output.periods_save.spectra = 1.0
+
+sim = Simul(params)
+sim.time_stepping.start()
+
+# Analyze energy cascade
+sim.output.spectra.plot1d(tmin=30.0, tmax=50.0)
+```
+
+### Stratified Flow Simulation
+
+```python
+from fluidsim.solvers.ns2d.strat.solver import Simul
+
+params = Simul.create_default_params()
+params.oper.nx = params.oper.ny = 256
+params.N = 2.0  # stratification strength
+params.nu_2 = 5e-4
+params.time_stepping.t_end = 20.0
+
+# Initialize with dense layer
+params.init_fields.type = "in_script"
+sim = Simul(params)
+X, Y = sim.oper.get_XY_loc()
+b = sim.state.state_phys.get_var("b")
+b[:] = exp(-((X - 3.14)**2 + (Y - 3.14)**2) / 0.5)
+sim.state.statephys_from_statespect()
+
+sim.time_stepping.start()
+sim.output.phys_fields.plot("b")
+```
+
+### High-Resolution 3D Simulation with MPI
+
+```python
+from fluidsim.solvers.ns3d.solver import Simul
+
+params = Simul.create_default_params()
+params.oper.nx = params.oper.ny = params.oper.nz = 512
+params.nu_2 = 1e-5
+params.time_stepping.t_end = 10.0
+params.init_fields.type = "noise"
+
+sim = Simul(params)
+sim.time_stepping.start()
+```
+
+Run with:
+```bash
+mpirun -np 64 python script.py
+```
+
+### Taylor-Green Vortex Validation
+
+```python
+from fluidsim.solvers.ns2d.solver import Simul
+import numpy as np
+from math import pi
+
+params = Simul.create_default_params()
+params.oper.nx = params.oper.ny = 128
+params.oper.Lx = params.oper.Ly = 2 * pi
+params.nu_2 = 1e-3
+params.time_stepping.t_end = 10.0
+params.init_fields.type = "in_script"
+
+sim = Simul(params)
+X, Y = sim.oper.get_XY_loc()
+vx = sim.state.state_phys.get_var("vx")
+vy = sim.state.state_phys.get_var("vy")
+vx[:] = np.sin(X) * np.cos(Y)
+vy[:] = -np.cos(X) * np.sin(Y)
+sim.state.statephys_from_statespect()
+
+sim.time_stepping.start()
+
+# Validate energy decay
+df = sim.output.spatial_means.load()
+# Compare with analytical solution
+```
+
+## Quick Reference
+
+**Import solver**: `from fluidsim.solvers.ns2d.solver import Simul`
+
+**Create parameters**: `params = Simul.create_default_params()`
+
+**Set resolution**: `params.oper.nx = params.oper.ny = 256`
+
+**Set viscosity**: `params.nu_2 = 1e-3`
+
+**Set end time**: `params.time_stepping.t_end = 10.0`
+
+**Run simulation**: `sim = Simul(params); sim.time_stepping.start()`
+
+**Plot results**: `sim.output.phys_fields.plot("vorticity")`
+
+**Load simulation**: `sim = load_sim_for_plot("path/to/sim")`
+
+## Resources
+
+**Documentation**: https://fluidsim.readthedocs.io/
+
+**Reference files**:
+- `references/installation.md`: Complete installation instructions
+- `references/solvers.md`: Available solvers and selection guide
+- `references/simulation_workflow.md`: Detailed workflow examples
+- `references/parameters.md`: Comprehensive parameter documentation
+- `references/output_analysis.md`: Output types and analysis methods
+- `references/advanced_features.md`: Forcing, MPI, parametric studies, custom solvers