Name: pyrestoolbox-mcp
Author: gabrielserrao

Imported from gabrielserrao/resEngineerAgent (SKILL/SKILL.md). Install upstream with npx skills add gabrielserrao/resEngineerAgent --skill SKILL. Copyright stays with the author.

pyResToolbox MCP Server — Agent Usage Guide

This skill teaches you how to effectively use the pyResToolbox MCP Server, which provides 108 production-ready reservoir engineering tools via the Model Context Protocol.

The server wraps the pyResToolbox Python library by Mark Burgoyne and is served through FastMCP.

Repository: https://github.com/gabrielserrao/pyrestoolbox-mcp

CRITICAL: Parameter Naming Conventions

Different tool families use different parameter names for similar concepts. Getting these wrong will cause validation errors. Pay close attention:

Pressure parameter names

Oil PVT tools: p (pressure array/scalar)
Gas PVT tools: p (pressure array/scalar)
Inflow tools: psd (sandface pressure) — NOT pwf or p
Nodal tools: pr (reservoir pressure inside ReservoirModel), thp (tubing head)
Geomech tools: pore_pressure, vertical_stress, etc.

Gas specific gravity parameter names

Oil tools: sg_g (gas specific gravity)
Gas tools: sg (gas specific gravity) — NOT sg_g or sg_gas
Inflow gas tools: sg — same as gas tools
Nodal tools: gas_sg

Method parameter names

gas_z_factor: parameter is method → "DAK", "HY", "WYW", "BUR"
gas_formation_volume_factor, gas_viscosity, gas_density, gas_compressibility: parameter is zmethod → "DAK", "HY", "WYW", "BUR" — NOT method
gas_critical_properties: parameter is method → "PMC", "SUT", "BUR", "BNS"
gas_delta_pseudopressure, create_gas_pvt: uses BOTH zmethod AND cmethod
Oil tools: parameter is method
Nodal tools: parameter is vlp_method → "HB", "WG", "GRAY", "BB"
Fracture gradient: parameter is method → "hubbert_willis", "eaton", "matthews_kelly"

Temperature parameter name

Most tools: degf (degrees Fahrenheit in field units)
Nodal ReservoirModel: degf
Nodal CompletionModel: wellhead_temp and bht
Matbal tools: temperature

Unit Systems

Every tool accepts a metric boolean parameter. Default is False (field units).

System	Pressure	Temperature	Length	Rate (oil)	Rate (gas)	GOR
Field	psia	°F	ft	STB/day	MSCF/day	scf/stb
Metric	barsa	°C	m	sm³/day	sm³/day	sm³/sm³

Set metric: true when the user provides metric values. Always state units in output.

Valid Method Codes — Complete Reference

These are the EXACT string values accepted by each Literal type. Using any other value will cause a Pydantic validation error.

Bubble Point / Solution GOR methods

Code	Method	Used in
`"STAN"`	Standing (1947)	oil_bubble_point, oil_solution_gor
`"VALMC"`	Valko & McCain (2003)	oil_bubble_point, oil_solution_gor
`"VELAR"`	Velarde (1997)	oil_bubble_point, oil_solution_gor

Default for bubble point: "VALMC". Default for solution GOR: "VELAR".

Oil FVF methods

Code	Method	Used in
`"MCAIN"`	McCain et al. (1988)	oil_formation_volume_factor
`"STAN"`	Standing (1947)	oil_formation_volume_factor

Default: "MCAIN". Note the spelling is MCAIN not MCCAIN.

Oil Viscosity methods

Code	Method	Used in
`"BR"`	Beggs & Robinson (1975)	oil_viscosity

Only "BR" is available. No alternatives.

Z-factor methods (parameter name varies — see above)

Code	Method	Used in
`"DAK"`	Dranchuk & Abou-Kassem (1975)	All gas tools
`"HY"`	Hall & Yarborough (1973)	All gas tools
`"WYW"`	Wang, Ye & Wu (2021)	All gas tools
`"BUR"`	Burgoyne/Nielsen/Stanko EOS (2025, SPE-229932)	All gas tools

Default: "DAK". Use "BUR" for hydrogen-containing or unusual gas mixtures.

Critical Properties methods

Code	Method	Used in
`"PMC"`	Piper, McCain & Corredor (1993)	gas_critical_properties
`"SUT"`	Sutton (1985)	gas_critical_properties
`"BUR"`	Burgoyne/Nielsen/Stanko (2025)	gas_critical_properties
`"BNS"`	Same as BUR (alternate name)	gas_critical_properties

Default: "PMC". Note: matbal tools accept "PMC", "SUT", "BUR" only (no "BNS").

VLP correlations (parameter: `vlp_method`)

Code	Method	Best for
`"WG"`	Woldesemayat-Ghajar	General (recommended)
`"HB"`	Hagedorn-Brown (1965)	Vertical oil wells
`"GRAY"`	Gray (1978)	Gas wells with condensate
`"BB"`	Beggs & Brill (1973)	General purpose, deviated

Default: "WG".

Relative Permeability families

Code	Method	Table Generation	Curve Fitting
`"COR"`	Corey (1954)	YES	YES
`"LET"`	Lomeland, Ebeltoft & Thomas	YES	YES
`"JER"`	Jerauld (2006)	NO	YES

IMPORTANT: "JER" is only valid for fit_relative_permeability, NOT for generate_rel_perm_table. Using "JER" for table generation will fail.

Rel perm table types (parameter: `krtable`)

Code	Description
`"SWOF"`	Water-oil table
`"SGOF"`	Gas-oil table
`"SGWFN"`	Gas-water function table

Decline Curve methods

Code	Method	When to use
`"exponential"`	Exponential decline	Boundary-dominated flow
`"harmonic"`	Harmonic decline	b=1 case
`"hyperbolic"`	Hyperbolic decline	General Arps (0<b<2)
`"duong"`	Duong (2011)	Tight/shale/unconventional
`"best"`	Auto-select (highest R²)	Let the tool pick

Note: For fit_decline_cumulative, "duong" is NOT available.

Ratio analysis methods

Code	Method
`"linear"`	Linear model
`"exponential"`	Exponential model
`"power"`	Power model
`"logistic"`	Logistic model
`"best"`	Auto-select (fitting only)

Geomech-specific Literal values

Fracture gradient method: "hubbert_willis", "eaton", "matthews_kelly" Fracture width model: "PKN", "KGD" Pore pressure method: "sonic", "resistivity" Dynamic-to-static correlation: "eissa_kazi", "plona_cook", "linear" Lithology: "sandstone", "shale", "carbonate" (some tools add "general") UCS correlation: "mcnally", "horsrud", "chang", "lal", "vernik" Shear failure criteria: "mohr_coulomb", "drucker_prager", "mogi_coulomb", "modified_lade", "modified_wiebols" Leak-off test type: "LOT", "FIT"

Component library EOS

Code	Method
`"PR79"`	Peng-Robinson 1979
`"PR77"`	Peng-Robinson 1977
`"SRK"`	Soave-Redlich-Kwong
`"RK"`	Redlich-Kwong

Default: "PR79".

Sensitivity analysis valid modules

"gas", "oil", "brine", "simtools", "layer", "library", "nodal", "matbal", "dca"

Parameter Validation Constraints

These are enforced by Pydantic and will cause errors if violated.

Oil parameters

Parameter	Constraint
`api`	gt=0, le=100
`degf`	gt=-460, lt=1000
`sg_g`	ge=0, le=3
`rsb`	ge=0
`p`	must be > 0 (validated)
`rs`	must be >= 0
`bo`	must be > 0
`nrows`	gt=0, le=200

Gas parameters

Parameter	Constraint
`sg`	ge=0.5, le=2.0
`degf`	gt=-460, lt=1000
`p`	must be > 0
`h2s`	ge=0.0, le=1.0
`co2`	ge=0.0, le=1.0
`n2`	ge=0.0, le=1.0
`h2`	ge=0.0, le=1.0

Inflow parameters

Parameter	Constraint
`pi`	gt=0
`pb`	ge=0
`psd`	must be > 0
`h`	gt=0
`k`	gt=0
`re`	gt=0
`rw`	gt=0, must be < re
`s`	any float (default 0.0)

Geomech parameters

Parameter	Constraint
`poisson_ratio`	gt=0, lt=0.5
`friction_angle`	gt=0, lt=90
`biot_coefficient`	gt=0, le=1
`porosity`	gt=0, lt=1
`wellbore_azimuth`	ge=0, le=360
`wellbore_inclination`	ge=0, le=90
`tectonic_factor`	ge=0, le=1

Rel perm parameters

Parameter	Constraint
`kromax`	ge=0, le=1
`krwmax`	ge=0, le=1
`krgmax`	ge=0, le=1
`swc`	ge=0, le=1
`sorw`	ge=0, le=1
`no`, `nw`	gt=0
`Lo`,`Eo`,`To`	gt=0

Rachford-Rice

Parameter	Constraint
`zis`	min 2 elements, all >= 0, sum ≈ 1.0
`Kis`	min 2 elements, all >= 0

DCA parameters

Parameter	Constraint
`qi`	gt=0
`di`	gt=0 (Arps), ge=0 (forecast)
`b`	ge=0, le=2
`m`	gt=1 (Duong)
`a`	gt=0 (Duong)

Nodal Analysis — Nested Object Structure

Nodal tools require nested Pydantic objects. You MUST pass them as nested dicts:

CompletionModel (required by most nodal tools)

{
  "tubing_id": 2.992,
  "tubing_length": 10000.0,
  "wellhead_temp": 80.0,
  "bht": 200.0,
  "roughness": 0.0006,
  "casing_id": 0.0,
  "metric": false
}

ReservoirModel (required by ipr_curve, operating_point)

{
  "pr": 4000.0,
  "degf": 180.0,
  "k": 100.0,
  "h": 50.0,
  "re": 1500.0,
  "rw": 0.354,
  "S": 0.0,
  "D": 0.0,
  "metric": false
}

Multi-segment completion (optional, overrides tubing_id/length)

{
  "segments": [
    {"md": 5000.0, "id": 4.5, "deviation": 0.0},
    {"md": 10000.0, "id": 2.992, "deviation": 30.0}
  ],
  "wellhead_temp": 80.0,
  "bht": 200.0
}

Tool Categories & Exact Call Signatures

1. Oil PVT Properties

Tool	Required Parameters	Optional (with defaults)
`oil_bubble_point`	api, degf, rsb	sg_g=0.0, method="VALMC", metric=false
`oil_solution_gor`	api, degf, p	sg_g=0.0, pb=0.0, rsb=0.0, method="VELAR", metric=false
`oil_formation_volume_factor`	api, degf, p	sg_g=0.0, pb=0.0, rs=0.0, rsb=0.0, method="MCAIN", metric=false
`oil_viscosity`	api, degf, p	pb=0.0, rs=0.0, rsb=0.0, method="BR", metric=false
`oil_density`	p, api, degf, rs, sg_g, bo	metric=false
`oil_compressibility`	p, api, degf, pb, sg_g, rs	rsb=0.0, metric=false
`oil_api_from_sg`	sg (oil specific gravity)	—
`oil_sg_from_api`	api	—
`generate_black_oil_table`	pi, api, degf, sg_g	pmax=0.0, pb=0.0, rsb=0.0, nrows=50, export=false, pb_method="VALMC", rs_method="VELAR", bo_method="MCAIN", uo_method="BR", metric=false
`create_oil_pvt`	api, sg_sp, pb, temperature, pressures[]	rsb=0.0, sg_g=0.0, uo_target=0.0, p_uo=0.0, rs_method="VELAR", pb_method="VALMC", bo_method="MCAIN", metric=false

Additional oil tools: oil_rs_at_bubble_point, evolved_gas_sg, stock_tank_gas_sg, oil_sg_from_jacoby, oil_twu_critical_properties, weighted_average_gas_sg, stock_tank_incremental_gor, validate_gas_gravities, oil_harmonize_pvt

2. Gas PVT Properties

Tool	Required Parameters	Optional (with defaults)
`gas_z_factor`	sg, degf, p	h2s=0.0, co2=0.0, n2=0.0, h2=0.0, method="DAK", metric=false
`gas_critical_properties`	sg	h2s=0.0, co2=0.0, n2=0.0, h2=0.0, method="PMC", metric=false
`gas_formation_volume_factor`	sg, degf, p	h2s/co2/n2/h2=0.0, zmethod="DAK", metric=false
`gas_viscosity`	sg, degf, p	h2s/co2/n2/h2=0.0, zmethod="DAK", metric=false
`gas_density`	sg, degf, p	h2s/co2/n2/h2=0.0, zmethod="DAK", metric=false
`gas_compressibility`	sg, degf, p	h2s/co2/n2/h2=0.0, zmethod="DAK", metric=false
`gas_pseudopressure`	sg, degf, p1, p2	h2s/co2/n2/h2=0.0, zmethod="DAK", metric=false
`gas_pressure_from_pz`	pz, sg, degf	h2s/co2/n2/h2=0.0, zmethod="DAK", metric=false
`gas_water_content`	p, degf	metric=false
`gas_sg_from_composition`	hc_mw	co2=0.0, h2s=0.0, n2=0.0, h2=0.0, metric=false
`gas_hydrate_prediction`	p, degf, sg	method="TOWLER", inhibitor_type=null, inhibitor_wt_pct=0.0, co2/h2s/n2/h2=0.0, p_res=null, degf_res=null, metric=false
`gas_sg_from_gradient`	grad, degf, p	metric=false
`gas_fws_sg`	sg_g, cgr, api_st	metric=false
`gas_delta_pseudopressure`	p1, p2, degf, sg	h2s/co2/n2/h2=0.0, zmethod="DAK", cmethod="PMC", metric=false
`create_gas_pvt`	pressures[], temperature	sg=0.75, co2/h2s/n2/h2=0.0, zmethod="DAK", cmethod="PMC", metric=false

WARNING: gas_z_factor uses method but other gas tools use zmethod. This is a common source of errors!

3. Well Performance & Inflow (uses `psd` for sandface pressure)

Tool	Required Parameters	Optional (with defaults)
`oil_rate_radial`	pi, pb, api, degf, sg_g, psd, h, k, re, rw	s=0.0, rsb=0.0, vogel=false
`oil_rate_linear`	pi, pb, api, degf, sg_g, psd, h, k, area, length	rsb=0.0
`gas_rate_radial`	pi, sg, degf, psd, h, k, re, rw	s=0.0, h2s=0.0, co2=0.0, n2=0.0
`gas_rate_linear`	pi, sg, degf, psd, h, k, area, length	h2s=0.0, co2=0.0, n2=0.0

CRITICAL: Parameter is psd (sandface pressure), NOT pwf. Using pwf will fail. The rw (wellbore radius) must be less than re (drainage radius) or validation fails.

4. Nodal Analysis (requires nested objects)

Tool	Required Parameters
`flowing_bhp`	thp, completion:{...}, vlp_method, well_type, + rate params
`ipr_curve`	reservoir:{...}, well_type
`outflow_curve`	thp, completion:{...}, vlp_method, well_type
`operating_point`	thp, completion:{...}, reservoir:{...}, vlp_method, well_type
`generate_vfp_prod_table`	table_num, completion:{...}, well_type, vlp_method
`generate_vfp_inj_table`	table_num, completion:{...}, flo_type

well_type: "gas", "oil" (for most), or "gas", "oil", "water" (for ipr_curve) flo_type (VFP injection only): "WAT", "GAS", "OIL"

5. Simulation Support

Tool	Required Parameters	Key Options
`generate_rel_perm_table`	(all optional with defaults)	krtable="SWOF"/"SGOF"/"SGWFN", krfamily="COR"/"LET" only
`fit_relative_permeability`	sw[], kr[]	krfamily="COR"/"LET"/"JER"
`fit_relative_permeability_best`	sw[], kr[]	Auto-selects best model
`generate_aquifer_influence`	(all optional)	start=0.01, end=1000, rows=25, res=10, infl="pot"/"press"
`rachford_rice_flash`	zis[], Kis[]	zis must sum to ~1.0
`generate_black_oil_table_og`	pi, api, degf, sg_g, pmax	Various optional params
`generate_pvtw_table`	pi, degf	wt=0.0, ch4_sat=0.0, pmin=500, pmax=10000, nrows=20
`extract_eclipse_problem_cells`	filename	silent=true
`validate_simulation_deck`	files2scrape[]	tozip=false, console_summary=true
`evaluate_jerauld`	s[], a, b	—
`check_let_physical`	s[], L, E, T	All L,E,T must be > 0

6. Decline Curve Analysis

Tool	Required Parameters	Key Options
`fit_decline`	time[], rates[]	method="best" (default), t_start, t_end
`fit_decline_cumulative`	cumulative_production[], rates[]	method="best", NO duong option
`decline_forecast`	qi, t_end	di=0.0, b=0.0, method="hyperbolic", dt=1.0, q_min=0.0, uptime=1.0, a/m for Duong
`arps_rate`	qi, di, b, t	—
`arps_cumulative`	qi, di, b, t	—
`estimated_ultimate_recovery`	qi, di, b, q_min	—
`duong_rate`	qi, a, m, t	m must be > 1
`fit_ratio`	x[], ratio[]	method="best", domain="cum"/"time"
`ratio_forecast`	method, a, b, x	c=0.0 (logistic), domain="cum"/"time"

7. Material Balance

Tool	Required Parameters	Key Options
`gas_material_balance`	pressures[], cumulative_gas[], temperature	gas_sg=0.65, z_method="DAK", c_method="PMC" (NO "BNS")
`oil_material_balance`	pressures[], cumulative_oil[], temperature	api, sg_sp, pb, rsb, rs_method="VELAR", bo_method="MCAIN", z_method="DAK", c_method="PMC"

NOTE: Matbal uses z_method and c_method (with underscore), NOT zmethod/cmethod.

8. Brine & CO₂ Properties

Tool	Required Parameters	Key Options
`calculate_brine_properties`	p, degf, wt (wt% NaCl, 0-30)	ch4=0.0, co2=0.0, metric=false
`co2_brine_mutual_solubility`	pres, temp, ppm	metric=false, cw_sat=0.0
`soreide_whitson_vle`	pres, temp	ppm=0.0, y_CO2/y_H2S/y_N2/y_H2=0.0, sg=0.65, metric=false

Note: Brine salinity uses wt (weight percent) in calculate_brine_properties but ppm in the other two tools. Don't mix them up.

9. Reservoir Heterogeneity

Tool	Required Parameters
`lorenz_to_beta`	value (float, 0-1)
`beta_to_lorenz`	value (float, 0-1)
`lorenz_from_flow_fractions`	flow_frac[], perm_frac[] (must sum to ~1.0)
`flow_fractions_from_lorenz`	flow_frac[], perm_frac[] (must sum to ~1.0)
`generate_layer_distribution`	lorenz (0-1), nlay (int)

10. Geomechanics (27 tools)

Read references/tools-reference.md for complete parameter details. Key tools:

Tool	Key Required Params	Key Literal Values
`geomech_vertical_stress`	depth	avg_density=144.0
`geomech_pore_pressure_eaton`	depth, observed_value, normal_value, overburden_psi	method="sonic"/"resistivity"
`geomech_horizontal_stress`	vertical_stress, pore_pressure, poisson_ratio	tectonic_factor=0.0
`geomech_fracture_gradient`	depth, vertical_stress, pore_pressure	method="hubbert_willis"/"eaton"/"matthews_kelly"
`geomech_safe_mud_weight_window`	pore_pressure, fracture_pressure, depth	safety margins
`geomech_breakdown_pressure`	sigma_h_max, sigma_h_min, pore_pressure	tensile_strength=0.0
`geomech_hydraulic_fracture_width`	net_pressure, fracture_height, fracture_half_length, youngs_modulus, poisson_ratio	model="PKN"/"KGD"
`geomech_ucs_from_logs`	(one of: sonic_dt, porosity, youngs_modulus)	lithology="sandstone"/"shale"/"carbonate"/"general", correlation="mcnally"/"horsrud"/"chang"/"lal"/"vernik"
`geomech_shear_failure_criteria`	sigma_1, sigma_2, sigma_3, ucs, cohesion, friction_angle	criteria=["mohr_coulomb","drucker_prager","mogi_coulomb","modified_lade","modified_wiebols"]
`geomech_dynamic_to_static_moduli`	dynamic_youngs or dynamic_poisson	correlation="eissa_kazi"/"plona_cook"/"linear", lithology="sandstone"/"shale"/"carbonate"

11. Utility Tools

Tool	Required Parameters
`get_component_properties`	component (string, e.g. "Methane", "C1", "CO2")
`recommend_methods`	(all optional)
`recommend_gas_methods`	(all optional)
`recommend_oil_methods`	(all optional)
`recommend_vlp_method`	(all optional)
`parameter_sweep`	function_module, function_name, base_parameters, vary_parameter, vary_values[]
`tornado_sensitivity`	function_module, function_name, base_parameters, ranges:{param: [low, high]}

Common Workflows

Workflow 1: Complete Oil PVT Analysis

oil_bubble_point → get Pb (pass api, degf, rsb, sg_g)
oil_solution_gor at multiple pressures → Rs profile
oil_formation_volume_factor → Bo
oil_viscosity → μo
oil_density → ρo (requires rs, sg_g, bo as inputs)
Or use generate_black_oil_table with pi, api, degf, sg_g to get everything at once

Workflow 2: Well Performance Study

oil_bubble_point → determine Pb
oil_rate_radial at several psd values → build IPR
Or use ipr_curve from nodal module (requires nested reservoir object)
outflow_curve → VLP curve (requires nested completion object)
operating_point → intersection of IPR and VLP

Workflow 3: Simulation Input Generation

generate_rel_perm_table with COR or LET → SWOF/SGOF tables
generate_black_oil_table or generate_black_oil_table_og → PVTO/PVDG
generate_pvtw_table → PVTW keyword
generate_aquifer_influence → AQUTAB
generate_vfp_prod_table / generate_vfp_inj_table → VFP tables

Workflow 4: Gas Reservoir Evaluation

gas_critical_properties → Tc, Pc (with contaminants h2s, co2, n2, h2)
gas_z_factor at multiple pressures → Z-factor profile (param: method)
gas_rate_radial → deliverability (param: psd for sandface pressure, sg for gas gravity)
gas_material_balance → OGIP from P/Z data (param: z_method, c_method)

Workflow 5: Geomechanics / Drilling

geomech_vertical_stress → overburden
geomech_pore_pressure_eaton → pore pressure
geomech_horizontal_stress → min/max horizontal stress
geomech_safe_mud_weight_window → safe drilling window
geomech_fracture_gradient → fracture initiation pressure

Workflow 6: CO₂ Sequestration Screening

calculate_brine_properties → formation brine baseline (salinity in wt%)
co2_brine_mutual_solubility → CO₂ solubility (salinity in ppm)
soreide_whitson_vle → multi-gas phase equilibrium

Best Practices for Error-Free Calls

Check parameter names against this document. The #1 source of errors is using wrong parameter names (pwf vs psd, method vs zmethod, sg vs sg_g).
Check enum values are exact strings. Must be EXACT: "VALMC" not "ValMC", "DAK" not "dak", "SWOF" not "swof".
Verify numeric constraints. API must be 0-100, gas SG must be 0.5-2.0, Poisson's ratio must be 0-0.5 (exclusive), friction angle 0-90 (exclusive).
Arrays must be valid. Pressures > 0, compositions sum to ~1.0 for Rachford-Rice, flow/perm fractions sum to ~1.0 for layer tools.
Use arrays for sweeps. Many tools accept arrays for pressure. Use this instead of calling the tool multiple times.
Compare correlations. Call the same tool with different method values and present the comparison as a table.
Chain tools for workflows. Use output of one tool as input to the next.
Use recommend tools first. Call recommend_oil_methods, recommend_gas_methods, or recommend_vlp_method if unsure which correlation to use.
Present results clearly. Format as tables with units in headers. Round pressure to 1 decimal, Bo to 4 decimals, viscosity to 2 decimals, Z-factor to 4 decimals.

Error Handling

Common errors and fixes:

Error	Cause	Fix
`Unknown parameter 'pwf'`	Wrong parameter name	Use `psd` for inflow tools
`Unknown parameter 'method'`	Wrong method param name	Use `zmethod` for gas Bg/μg/ρg/cg
`Input should be 'DAK', 'HY', 'WYW' or 'BUR'`	Wrong Literal value	Check exact string in method table above
`Gas specific gravity must be >= 0.5`	sg out of range	Ensure 0.5 ≤ sg ≤ 2.0
`Wellbore radius must be < drainage radius`	rw >= re	Make rw < re
`Mole fractions must sum to 1.0`	Composition doesn't sum	Ensure zis sums to ~1.0
`All pressure values must be positive`	Negative/zero pressure	Ensure all pressures > 0
`krfamily 'JER' not valid`	JER used for table generation	Only use COR or LET for generate_rel_perm_table

References

For the complete parameter reference of all 108 tools, read:

references/tools-reference.md — Full tool signatures with every parameter, type, constraint, and default

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