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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered structurally. The description adds the conceptual point that names are canonicalized across brokers plus a sample filter value, but says nothing about pagination, scope (all brokers vs. current workspace), or result volume.

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?

Three short sentences with no filler, and the core differentiator (canonical naming) is front-loaded. The wording is slightly elliptical, but nothing is redundant.

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?

An output schema exists, so return-shape explanation is unnecessary, and annotations cover the safety profile. The description supplies the one thing structured fields cannot: the relationship to list_account_instruments and the canonical-vs-broker naming distinction.

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 both parameters are enums with their own descriptions, so the schema carries the semantics. The example {"category": "metals"} shows a valid usage but adds no constraints (defaults, multi-value, required-ness) beyond the schema.

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 conveys the resource clearly — canonical market names (XAUUSD, US30, BTCUSD) as opposed to each broker's own naming — and explicitly contrasts it with list_account_instruments. It never states the verb outright ('list'/'returns'), so the action is inferred from the tool name rather than the prose.

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 names the sibling alternative list_account_instruments and what that sibling returns ('one account's own symbol for each'), which effectively tells the agent which of the two to pick. There is no explicit 'use this when / not when' framing, and no mention of prerequisites, but the selection context is clear.

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