3GPP Expert / skill
3GPP Expert / skill
GSM through 6G. Every release from Phase 1 to Rel 21. Protocol stacks, core network, spectrum strategy, security — answered at standards level and cited to the TS that carries it.
Answers come from Claude running this skill's instructions in your browser session. No web search here, so anything past the model's training is flagged rather than guessed.
Synchronisation signals are where telecom answers quietly fall apart — the sequences are similar, the naming overlaps, and a confident wrong answer looks identical to a right one. The skill pins them.
Releases land on a roughly 2.5-year cycle, each carrying hundreds of specifications. The skill knows what every one of them introduced and why it mattered.
PHY numerologies and BWPs, MAC scheduling and HARQ, RLC modes, PDCP integrity, SDAP QoS-flow mapping, RRC state machines — always with the LTE-to-NR delta called out.
The service-based architecture end to end: AMF, SMF, UPF, PCF, UDM, NRF, NEF — plus what each one replaced on the EPC side.
NSA versus SA option sets, migration paths on a budget, link budgets, cell planning, interference, spectrum strategy, O-RAN split options.
EPS-AKA and 5G-AKA, SUPI concealment, what an IMSI catcher can and cannot still do against a 5G SA network.
| File | What it carries |
|---|---|
| SKILL.md | Main instructions — seven knowledge domains, critical PHY facts, response patterns, when to reach for web search |
| references/releases.md | Release-by-release reference, Phase 1 through Rel-21, with the full specification series table |
| references/phy-layer.md | PHY deep dive — sync signals per RAT, physical channels, reference signals, RACH preambles, channel mapping |
| references/working-groups.md | RAN / SA / CT working group structure, the specs each one owns, typical topics |
3gpp-expert.skill from Releases.~/.claude/skills/3gpp-expert/
├── SKILL.md
└── references/
├── releases.md
├── phy-layer.md
└── working-groups.md