Paid tier only. Calling this without an authenticated CivilQuants account returns TIER_INSUFFICIENT — sign up at https://civilquants.com/pricing or use the free-tier alternative compute_cantilever_wall. Anchored retaining wall — the only wall family member that pre-stresses the retained soil mass into the wall via post-tensioned ground anchors per BS EN 1537. Three structural variants: in-situ reinforced concrete (INSITU_RC, economic 5-10m); steel king-post-and-lagging (KING_POST, typical 4-8m, often temporary); driven sheet pile (SHEET_PILED, quays/cofferdams/deep basements). Eight VARIANT_PRESETS exercise the 'one parameter form, eight variants, four standards' moat #1 claim across all three structural variants. The in-situ RC body routes via wall_type='anchored' attribute discrimination: CESMM4 F.6.4, NRM2 11.3.4, MMHW 1700.4.3 (SHW Cl. 1709/1710), SMM7 E10.3.3. Ground anchors and stressing route to new specialist handlers (CESMM4 Class C; NRM2 Group 7; MMHW Series 1600; SMM7 D32). King-post sections to CESMM4 P.5 / NRM2 7.3 / MMHW 1600.3 / SMM7 D32; sheet piles to CESMM4 P.4 / NRM2 7.4 / MMHW 1600.4 / SMM7 D31; timber lagging to CESMM4 O.3 / NRM2 16.4 / MMHW 2500.7 / SMM7 G20.1. Example params: stem_height=6 m (2–15), stem_thickness=0.5 m (0–1.5), wall_length=25 m (5–200). Example call: {"params": {"stem_height": 6, "stem_thickness": 0.5, "wall_length": 25}, "standard": "MMHW"}. Omitted parameters use sensible engineering defaults. Pass deliverables=["xlsx","dxf","pdf"] (any subset) to also receive one-shot download URLs in the same call: Excel BoQ (both tiers, watermarked free) plus the dimensioned DXF (CAD) and PDF drawing sheets (paid tier). Pass `freeboard` (clearance below the wall top, m) instead of the retained-height field to set the retained fill by clearance — the engine back-calculates it as stem − freeboard. Supplying both is rejected.