Checks which market data is available for one exact symbol by returning its coverage rows. Use it to confirm a symbol has crypto or equity data before querying or replaying.
Inventory coverage rows for one exact symbol.
| Name | Required | Description | Default |
|---|---|---|---|
| source | No | ||
| symbol | Yes | ||
| channel | No | ||
| asset_class | No | Which market answers. Inferred from the symbol's source when omitted. |
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. 'Inventory' weakly implies a read operation, but the description does not disclose permissions, response behavior, filtering behavior, error cases, or what a coverage row represents.
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?
The description is a single front-loaded sentence with no wasted text. It is concise, though its brevity contributes to the larger under-specification problem.
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?
For a four-parameter tool with no annotations, no output schema, and low schema description coverage, this is insufficient. An agent cannot tell what coverage rows are, how source/channel filtering works, or what to expect from the result.
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 25%, so the description needs to compensate. It clarifies that the symbol must be exact and singular, but says nothing about the source or channel filters, nor does it explain how asset_class inference interacts with those filters.
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?
The description states a resource, 'coverage rows,' and a scope, 'one exact symbol,' but 'inventory coverage' is vague without defining what coverage means or what rows contain. It does not distinguish this tool from nearby catalog/inventory siblings.
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?
The only usage signal is 'one exact symbol,' which implies exact-match lookup rather than prefix or bulk search. There is no explicit when-to-use guidance, no exclusions, and no named alternatives among the many catalog/list siblings.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.