MCP server for Exostream LLM pricing oracle - get real-time inference costs for Claude, GPT, Gemini, and more
Four tools with clear naming (verb_noun pattern) and solid descriptions (150-250 chars, well above 20-char minimum). All tools have complete input schemas with typed properties and descriptions. However, output schemas are entirely undocumented, LLMs cannot predict return structure. No error handling guidance, no parameter constraints (enums), no pagination support despite compare_models likely returning large result sets. Missing idempotency hints and recovery guidance. Descriptions are good but lack 'when to use' context and dependency hints between tools.
Compare all models for a task profile, ranked by cost. Returns models sorted cheapest to most expensive that can handle the input size. Use this to find the cheapest model for your workload.
Get complete Greek sheet for a model including theta and sigma. Parameters returned: - r_in: Input/output price ratio - r_cache: Cache discount ratio - r_think: Thinking token ratio (reasoning models) - theta: Monthly price decay rate - sigma: Realized monthly volatility Use this to understand pricing structure and expected cost decay.
Get current spot prices for LLM models from the Exostream oracle. Returns ticker, provider, sync/batch prices, and context window. Use this to: - Check current pricing for models - Compare prices across providers - See which models have batch pricing
Calculate the cost of an inference task. Returns spot cost in USD, kappa (price sensitivity), and cache savings. Formula: S = beta × [n_out + n_in × r_in_eff] × 10^-6 Kappa tells you how many times more expensive your task is vs pure output.
No output schemas documented. LLMs cannot predict return structure (fields, types, nesting). Responses are JSON-stringified text, forcing LLMs to parse unstructured output.
provider parameter in get_spots accepts free-form string with no enum constraint. Description lists valid values ('anthropic, openai, google, xai, mistral, deepseek') but LLMs may hallucinate alternatives.
No pagination support. compare_models returns all matching models without limit or offset. Large result sets will exhaust context window and degrade LLM reasoning.
Error handling returns raw API errors without recovery guidance. 'API error: 404 Not Found' tells LLM nothing about what to do next (retry? call different tool? ask user?).
| Scored | Grade | Overall | Spec posture | Rubric |
|---|---|---|---|---|
| 2026-09-23 | C | 62 | 2026-07-28+ | v2 |
No tool composition hints. Descriptions don't explain when to call get_spots vs get_greeks vs price_task, or how results chain together. LLMs must infer intent.