Module compression 

Compression statistics tracking across three layers.

Layers

• tokenless (external hook/rewrite): reported via TOKENLESS_TOKENS env var
• compress middleware (agent-proxy): SchemaCompressor + ResponseCompressor
• upstream (API response): usage fields extracted by cost module

Data flow

tokenless env var → parse → CompressionStats → ctx.extensions
  → compress middleware appends schema/response stats
  → cost module reads to compute saved_cost

Structs

CompressionStats

Complete multi-layer compression statistics.

Functions

read_tokenless_stats

Parses the TOKENLESS_TOKENS environment variable into CompressionStats.