Guide
How the kit works
Enter with Loong's Halo (Intro Skill) when possible. Outside Incarnation, it makes Overflowing Radiance (Resonance Skill) available for 5 seconds. You can also unlock it with the fourth hit of Slash of Breaking Dawn (Basic Attack). Use Overflowing Radiance to deal Spectro DMG and enter Incarnation.
In Incarnation, use Incarnation - Basic Attack (Basic Attack) through its fourth hit. Those attacks deal Spectro DMG counted as Resonance Skill DMG, and their attack cycle does not reset. Crescent Divinity (Resonance Skill) is also available in this state. After the fourth hit, Incarnation ends and Jinhsi gains Ordination Glow.
While Ordination Glow lasts, use Illuminous Epiphany (Resonance Skill). It consumes up to 50 Incandescence to increase the multiplier of its delayed Stella Glamor hit. Casting it grants Unison, at most once every 25 seconds. Switch while Unison is active to trigger Temporal Bender (Outro Skill) and the incoming character's Intro Skill. If Concerto Energy is full, Unison is consumed first.
Temporal Bender makes Incandescence generation from the same Attribute more frequent for 20 seconds. Purge of Light (Resonance Liberation) deals Spectro DMG and can be cast in mid-air. Tune Break: Broadblade is available when the target's Off-Tune Level is full.
Build and why
The game's build recommends five pieces of Celestial Light. Its listed two-piece effect gives 10% Spectro DMG, which suits Jinhsi's attacks. The supplied data does not describe the five-piece effect, so don't assume another bonus from it.
Ages of Harvest is the first weapon choice. It gives 12% Attribute DMG Bonus; its separate Intro Skill and Resonance Skill effects each give 24% Resonance Skill DMG Bonus for 12 seconds. That fits both Incarnation's basic attacks and Illuminous Epiphany (Resonance Skill).
Radiance Cleaver is the next option named by a guide. It gives 12% ATK and can grant Resonance Liberation Bonus against a target under Tune Strain - Interfered. Lustrous Razor offers Energy Regen and builds Resonance Liberation DMG Bonus when Jinhsi casts her skill. Autumntrace is a four-star alternative with an ATK effect triggered by Basic Attack DMG or Heavy Attack DMG. ATK and Spectro DMG are useful stats to consider, though no stat priority is supplied.
Leveling priority
I would level Luminal Synthesis first because it contains the Incarnation attacks and Illuminous Epiphany (Resonance Skill), the main attack you build Incandescence for. Trailing Lights of Eons (Resonance Skill) is a good next choice, followed by Purge of Light (Resonance Liberation). Leave Slash of Breaking Dawn (Basic Attack) and Loong's Halo (Intro Skill) until later.
For maximum ascension, gather 170,000 Shell Credit, 4 LF Howler Core, 12 MF Howler Core, 12 HF Howler Core, 4 FF Howler Core, 46 Elegy Tacet Core and 60 Loong's Pearl.
Maxing all skills separately takes 2,030,000 Shell Credit, 25 LF Howler Core, 28 MF Howler Core, 40 HF Howler Core, 57 FF Howler Core, 26 Sentinel's Dagger, 25 Waveworn Residue 210, 28 Waveworn Residue 226, 55 Waveworn Residue 235 and 67 Waveworn Residue 239.
Resonance Chain nodes worth it
Abyssal Ascension (sequence 1) is an earlier upgrade worth considering. Incarnation - Basic Attack (Basic Attack) and Crescent Divinity (Resonance Skill) build up to four stacks, each increasing Illuminous Epiphany's damage by 20% when consumed. Celestial Incarnate (sequence 3) gives 25% ATK per stack after Loong's Halo (Intro Skill), up to two stacks for 20 seconds.
Chronofrost Repose (sequence 2) restores 50 Incandescence after more than 4 seconds out of combat, so you can skip it if that convenience is not important to you. Benevolent Grace (sequence 4) gives nearby teammates 20% Attribute DMG Bonus for 20 seconds after Purge of Light (Resonance Liberation) or Illuminous Epiphany. Frostfire Illumination (sequence 5) instead increases the Liberation's multiplier.
Teams
Look for teammates who can deal Attribute DMG and Coordinated Attack DMG while Jinhsi's Incandescence is building. Normally, damage of the same Attribute can generate one point once every 3 seconds, while Coordinated Attacks of that Attribute can generate two points on a separate 3-second limit. Different Attributes have separate limits.
After Illuminous Epiphany (Resonance Skill), Unison lets Jinhsi switch into the next character with both transition skills triggered. Temporal Bender (Outro Skill) improves the same-Attribute generation interval to once every 1 second for 20 seconds, helping the team prepare her next attack.
Common mistakes
Don't cast Illuminous Epiphany (Resonance Skill) without checking Incandescence. It can still deal damage with fewer points, but consumes up to 50 to increase its multiplier. Give teammates time to build the resource when the fight allows it.
Don't stop the Incarnation attack chain before its fourth hit and expect Ordination Glow. You also have only 5 seconds to use Overflowing Radiance (Resonance Skill) after the qualifying Intro Skill or fourth normal basic attack.
Don't assume Unison is available after every cast: its trigger has a 25-second limit. When it is active, remember that switching consumes it before full Concerto Energy. Finally, don't count Incarnation's basic attacks as Basic Attack DMG when judging bonuses: their damage is considered Resonance Skill DMG.