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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint, so safety is covered. The description adds real value beyond that by disclosing the data semantics of the result: shares are absolute values and the side field carries long/short direction, which an agent could not infer from annotations alone.

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 tight sentences with the read-only qualifier and scope front-loaded, followed by the data-shape clarification. No filler or repetition.

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?

With no output schema, the description does useful work explaining the result shape (row-per-account-and-instrument, absolute shares, side field). For a no-required-parameter read tool with full annotation coverage, that is nearly sufficient; a note on ordering or whether closed positions are excluded would make it complete.

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% and the single 'broker' parameter is fully documented in the schema ('One broker id, such as ibkr or robinhood. Omit for every broker.'). The description adds no parameter-level information beyond that, so the baseline of 3 applies.

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?

States a specific verb+resource (read open positions) and pins down the scope: only brokers the user connected in Gloom. The row granularity ('one row per account and instrument') lets an agent distinguish it from portfolio.accounts and portfolio.performance without opening schemas.

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?

No explicit when-to-use or when-not-to-use guidance, and no mention of the sibling tools portfolio.accounts or portfolio.performance that an agent might confuse this with. Usage is only implied by the scope phrase 'at the brokers the user connected'.

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