Add a trading asset to your Alpaca watchlist by specifying the watchlist ID and the symbol you want to track.
Add an asset by symbol to a specific watchlist.
| Name | Required | Description | Default |
|---|---|---|---|
| symbol | No | the symbol name to add to the watchlist | |
| watchlist_id | Yes | watchlist id |
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
Changes observed during successful MCP inspections.
v2.3.2Input schema / properties / symbol / x-stoplightRemoved value: -{
- "id": "wb0v0f7q0ms5e"
-}v2.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full burden. It only states the action 'Add' with no details about idempotency, failure behavior, whether it appends or replaces, or any side effects. For a write operation, this is insufficient behavioral disclosure.
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, well-front-loaded sentence. Every word adds meaning, and there is no redundant or filler content. It is appropriately concise for a simple operation.
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?
Given the tool's simplicity, complete schema coverage, and presence of an output schema, the description is minimally sufficient. However, it lacks any behavioral context or guidance about interaction with sibling tools, making it only complete enough for a straightforward selection but not for understanding side effects or error conditions.
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 coverage is 100%, with both parameters described in the schema. The description adds minimal meaning beyond the schema, only tying 'by symbol' to the asset and 'specific watchlist' to the watchlist_id. It does not add syntax or additional semantics, so baseline 3 is appropriate.
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 uses a specific verb 'Add' with a clear resource ('an asset by symbol') and destination ('a specific watchlist'). It clearly distinguishes this from sibling tools like remove_asset_from_watchlist_by_id and update_watchlist_by_id.
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 description implies the usage context (adding an asset to a watchlist) but does not explicitly state when to use this tool versus alternatives. It does not mention prerequisites like needing an existing watchlist or that the asset must be known, nor does it reference the opposing remove operation.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.