get_positions

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnly/idempotent/non-destructive, so the safety bar is low. Beyond them, the description discloses the result ordering ('Sorted by market value') and that quote fetching yields 'live last/mark prices', which is genuine behavioral context. It still doesn't note the added latency or extra request cost of include_quotes=true.

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?

Two dense sentences with no filler: the field inventory and sort behavior come first, and the optional live-quote toggle is placed last. Every clause carries information an agent can act on.

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?

This is a simple read-only tool with all parameters documented and an output schema that carries the return shape, so the description does not need to define return values in detail. The gaps, mainly routing guidance versus get_portfolio_summary, are modest.

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 100%, so all three parameters (symbol, account, include_quotes) are already documented in the schema, establishing a baseline of 3. The description's note about include_quotes adding live last/mark prices partially duplicates the schema's 'adds a `live` block' text and adds little beyond it.

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 specific resource (holdings per account) and enumerates the returned fields (quantity, average cost, market value, unrealized and today's P/L, weight), which lets an agent tell it apart from generic siblings like get_portfolio_summary. However, it never names a sibling or explicitly contrasts itself with the portfolio/summary tools.

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?

It gives one inline usage instruction ('Set include_quotes=true for live last/mark prices'), which is helpful but only covers one parameter choice. There is no guidance on when to prefer this over get_portfolio_summary, get_orders, or get_transactions, and no stated prerequisites or exclusions.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.