Cutting insert and tool for machining

A tool for machining a workpiece, having a cutting insert and a cutting insert holder for holding the cutting insert, wherein the cutting insert comprises:

• a clamping section which comprises at least one coolant channel configured as a through-hole;
• a cutting head having at least one cutting member which comprises a main cutting edge, a rake face which adjoins the main cutting edge, and a chip-breaking geometry which protrudes from the rake face or which is introduced into the rake face and which is configured to break a chip which is machined with the main cutting edge;
• and
• a cantilever arm which extends along a longitudinal axis of the cutting insert and connects the clamping section to the cutting head and which has a smaller diameter than the clamping section;
• wherein the cutting insert is configured in a monolithic manner so that the clamping section, the cutting head and the cantilever arm are integrally connected to each other;
• and
• wherein a portion of the cutting head comprising the chip-breaking geometry, when viewed along the longitudinal axis of the cutting insert, covers at least 10% of a cross section of the coolant channel, but a maximum of 80% of the cross section of the coolant channel.