Lists per-symbol market data coverage for crypto or equities, showing source, channel, timestamps, and row counts so you can verify what is available before querying or replaying.
Per-symbol coverage rows: exchange, channel, symbol, timestamps, row count.
| Name | Required | Description | Default |
|---|---|---|---|
| source | No | ||
| channel | No | ||
| asset_class | Yes | Which market answers. Required: this tool has an implementation for each of these and no symbol parameter to infer one from. |
Changes observed during successful MCP inspections.
v0.3.2Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full behavioral burden, yet it only lists output columns. It never states that this is a non-destructive read, whether results are paginated or bounded, how large an unfiltered inventory can be, or what the caller gets when no data exists for a venue.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
A single front-loaded fragment with no filler, but it is under-specified rather than concise — it reads like a field list lifted from a return type rather than a complete tool description.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
A filterable catalog query with three parameters, one required, no output schema and no annotations needs the description to explain filters, scope and result shape. Listing five columns is not enough to call the tool correctly or distinguish it from catalog-symbols/catalog-scan.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is only 33%, and the one described parameter (asset_class) is documented in the schema, not the tool description. The description says nothing about source, channel, or how required asset_class constrains the answer, so it fails to compensate for the coverage gap.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
"Per-symbol coverage rows: exchange, channel, symbol, timestamps, row count" conveys the shape of the payload but never states a verb or what the tool actually does — list, summarize, inspect coverage? Given siblings like catalog-symbols, catalog-dates, catalog-stats and catalog-summary, an agent cannot tell from this fragment which one to reach for.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
There is no when-to-use guidance, no exclusions, and no reference to any of the many catalog-* siblings that overlap in scope. The agent is left to infer selection from the name alone.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.