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

Annotations already declare destructiveHint=true and idempotentHint=true, and the description adds genuinely new context: the previous list is retained as a server-side backup, and the response enumerates exactly what changed. It does not mention error behavior for invalid symbols, so it stops short of full 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?

Four short sentences, front-loaded with the core action and cap, then format guidance, then behavioral notes. Minor redundancy between "the user's Fair Value Calculator account" and "their own account," but no wasted sentences.

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 single-parameter mutation with no output schema and full annotation coverage, the description covers scope, symbol format, reversibility, and response shape. Only failure modes for bad symbols are unaddressed, which is a minor gap.

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%, so the array shape, min/max items, and item type are already documented. The description still adds cross-tool meaning by telling the agent to pass symbols "exactly as get_watchlist shows them," which is actionable guidance the schema alone does not provide.

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 (remove stocks from the watchlist) plus the owning account, which immediately distinguishes it from the add_to_watchlist sibling. The 10-item cap and the get_watchlist reference further pin down the operation.

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?

"Use it when the user asks for this change to their own account" gives clear positive usage context and implicitly routes away from read-only siblings like get_watchlist. It stops short of naming add_to_watchlist as the inverse or stating when not to use it, so no explicit exclusions.

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