| name | virtuoso |
| description | Bridge to remote Cadence Virtuoso: SKILL execution, layout/schematic editing, ADE Maestro simulation setup via Python API. TRIGGER when the user mentions Virtuoso, SKILL (the Cadence language), Cadence IC, layout editing, schematic creation, cellview operations, CIW commands, ADE setup, Maestro configuration, design variables, OCEAN results, or any EDA task involving a Cadence design database — even if they just say 'draw a circuit' or 'place some transistors'. |
Virtuoso Skill
How it works
You control a remote Cadence Virtuoso instance through virtuoso-bridge — a Python client that sends SKILL commands to the running Virtuoso CIW over a persistent connection. You write Python locally; Virtuoso executes SKILL remotely. SSH tunneling and daemon management are handled automatically by VirtuosoClient.from_env() — just configure .env with the remote host info and it works.
VirtuosoClient and SpectreSimulator (see the spectre skill) are independent clients. You don't need one to use the other.
The bridge supports three levels of abstraction (highest to lowest):
| Level | When to use | Example |
|---|
Python API (client.layout.*, client.schematic.*) | Layout/schematic editing — structured, safe, handles context manager | client.layout.edit(lib, cell) |
Inline SKILL (client.execute_skill(...)) | ADE control, CDF params, anything the Python API doesn't cover | client.execute_skill('maeRunSimulation()') |
SKILL file (client.load_il(...)) | Bulk operations, complex procedures — keeps payloads small | client.load_il("my_script.il") |
Use the highest level that covers your need. Drop to a lower level only when the higher one doesn't have the method.
Before you start
- Check connection: run
virtuoso-bridge status. If unhealthy: virtuoso-bridge restart.
- Check examples first: look at
examples/01_virtuoso/ below — if similar functionality exists, use it as a basis rather than writing from scratch.
- Open the window: call
client.open_window(lib, cell, view="layout") so the user can see what you're doing in the GUI.
Core patterns
Client setup
from virtuoso_bridge import VirtuosoClient
client = VirtuosoClient.from_env()
Schematic editing
with client.schematic.edit(lib, cell) as sch:
sch.add_instance("analogLib", "vdc", (0, 0), "V0", params={"vdc": "0.9"})
sch.add_instance("analogLib", "gnd", (0, -0.5), "GND0")
sch.add_wire_between_instance_terms("V0", "MINUS", "GND0", "gnd!")
sch.add_pin("VDD", "inputOutput", (0, 1.0))
Use terminal-aware helpers (add_wire_between_instance_terms, add_net_label_to_instance_term) instead of guessing pin coordinates — they resolve positions from the database. See references/schematic.md for full API.
Layout editing
with client.layout.edit(lib, cell) as layout:
layout.add_rect("M1", "drawing", (0, 0, 1, 0.5))
layout.add_path("M2", "drawing", [(0, 0), (1, 0)], width=0.1)
layout.add_instance("tsmcN28", "nch_ulvt_mac", (0, 0), "M0")
layout.add_via("M1_M2", (0.5, 0.25))
For large edits: split into chunks — first call with mode="w" (create), then mode="a" (append). Screenshot after layout work to verify visually. See references/layout.md for full API.
Inline SKILL (for anything beyond the Python API)
client.execute_skill('dbOpenCellViewByType("myLib" "myCell" "layout")')
SKILL file (for bulk / complex operations)
client.load_il("my_script.il")
client.execute_skill('myCustomFunction("arg1" "arg2")')
Put loops in .il files rather than sending giant SKILL strings — keeps each request payload small while the heavy loop runs inside Virtuoso.
File transfer and other operations
VirtuosoClient is the only client that exposes file transfer to the user. SpectreSimulator handles its own file transfer internally during run_simulation().
client.upload_file(local_path, remote_path)
client.download_file(remote_path, local_path)
client.open_window(lib, cell, view="layout")
client.get_current_design()
client.save_current_cellview()
client.close_current_cellview()
client.run_shell_command("ls /tmp/")
ADE control (Maestro)
Quick pattern — open session, configure, run, read results:
ses = client.execute_skill(f'maeOpenSetup("{lib}" "{cell}" "maestro")').output.strip('"')
client.execute_skill(f'maeCreateTest("AC" ?lib "{lib}" ?cell "{cell}" ?view "schematic" ?simulator "spectre" ?session "{ses}")')
client.execute_skill(f'maeSetAnalysis("AC" "ac" ?enable t ?options `(("start" "1") ("stop" "10G") ("dec" "20")) ?session "{ses}")')
client.execute_skill(f'maeSaveSetup(?lib "{lib}" ?cell "{cell}" ?view "maestro" ?session "{ses}")')
client.execute_skill('maeRunSimulation()')
client.execute_skill("maeWaitUntilDone('All)")
For the full API (variables, outputs, specs, corners, OCEAN results, history display), read references/ade.md. See examples/01_virtuoso/ade/01_rc_filter_sweep.py for the complete workflow.
References
Load only when needed — these contain detailed API docs and edge-case guidance:
references/schematic.md — schematic API, terminal-aware helpers, CDF parameter settingreferences/layout.md — layout API, read/query, mosaic, layer controlreferences/ade.md — ADE Maestro mae* API, OCEAN results, corners, simulation controlreferences/netlist.md — CDL/Spectre netlist formats, spiceIn import, netlist export
Existing examples
Always check these before writing new code. If similar functionality exists, use it as a basis.
examples/01_virtuoso/basic/
01_execute_skill.py — run arbitrary SKILL expressions02_load_il.py — upload and load .il files03_list_library_cells.py — list libraries and cells04_screenshot.py — capture layout/schematic screenshots
examples/01_virtuoso/schematic/
01a_create_rc_stepwise.py — create RC schematic via operations01b_create_rc_load_skill.py — create RC schematic via .il script02_read_connectivity.py — read instance connections and nets03_read_instance_params.py — read CDF instance parameters05_rename_instance.py — rename schematic instances06_delete_instance.py — delete instances07_delete_cell.py — delete cells from library08_import_cdl_cap_array.py — import CDL netlist via spiceIn (SSH)
examples/01_virtuoso/layout/
01_create_layout.py — create layout with rects, paths, instances02_add_polygon.py — add polygons03_add_via.py — add vias04_multilayer_routing.py — multi-layer routing05_bus_routing.py — bus routing06_read_layout.py — read layout shapes07–10 — delete/clear operations
examples/01_virtuoso/ade/
01_rc_filter_sweep.py — full Maestro workflow: create schematic, AC analysis, parametric sweep, bandwidth spec, display results
Related skills
- spectre — standalone netlist-driven Spectre simulation (no Virtuoso GUI). Use when the user has a
.scs netlist and wants to run it directly.
