Does capsule size 0 define a complete dimensional tolerance?
No. A size label groups a format; a specification identifies particular cap and body features and their stated ranges. Diameters, component lengths and joined length remain separate dimensions. Nominal size alone does not establish every tooling clearance or incoming-inspection criterion.
Identify the supplier, shell design and material, measured feature and joining state: open, prelocked or fully joined. Moisture and exposure conditions can affect shell dimensions, so retain conditioning and method with the value rather than assuming one global measurement condition.
Not automatically. A published diameter may be guidance for packaging evaluation, while a joined length may be a machine-setup recommendation. Neither becomes an incoming-shell approval or rejection limit without the applicable specification and its stated purpose.
For purchasing, obtain the current agreed drawing/specification and its inspection method rather than converting a public table into a universal release standard. A supplier range, a nominal target, measurement uncertainty and a tolerance are different pieces of information. They need to be connected to the actual decision, not silently substituted for one another.