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

With no annotations, the description carries the full burden and does so notably well: it discloses a non-obvious side effect (review reminder emails at 45 and 90 days, and at +10%) and an auth requirement ('Requires an InsideREU API key'). It omits rate limits and return behavior, keeping it short of a 5.

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, front-loaded with the core action before the behavioral details. Every clause earns its place, though the real/paper parenthetical slightly duplicates the schema's kind 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?

For an 8-parameter save tool with full schema documentation and no output schema, the description supplies the crucial behavioral facts an agent needs (email side effects, API-key auth). It is fairly complete, with only response/confirmation behavior left unstated.

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 the schema already documents all eight parameters including the kind enum and currency defaults. The description only echoes the real/paper choice and adds no format or syntax detail beyond the schema, which is the baseline 3.

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 and resource ('Save a trade to YOUR portfolio') and immediately clarifies the real-vs-paper distinction. An agent can distinguish this write/save operation from read siblings like list_my_trades and from the state-changing close_trade.

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 a selection condition for the real/paper choice ('the user says they bought it' = real), which is useful. But it says nothing about when to prefer this over siblings such as close_trade, and offers no prerequisites or exclusion conditions.

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