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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description adds real domain context beyond that: it is watch-only, holds no keys, and returns no balances, which prevents a common misuse. It stops short of return format or result-size hints, keeping it a 4 rather than 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?

Front-loaded with the resource and its value proposition, then the alternatives, with no filler sentences. The middle field enumeration is dense and long-ish, but it earns its place because there is no output schema.

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 compensates by listing the returned fields, and it flags the supportedChains/balanceOnly nuance an agent would otherwise misread. Sibling routing and scope exclusions are all present, so nothing needed to call this correctly is missing.

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?

The single `profile` parameter is fully documented in the schema (100% coverage, including fallback behavior and the profile_not_found/profile_ambiguous errors), and the description says nothing about it. With the schema doing all the work, the baseline 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 and resource ('List the on-chain addresses the user tracks') and enumerates exactly what each entry contains (address, label, wallet family, chains scanned, added date, enabled flag, plus supportedChains). It explicitly separates itself from get_portfolio and get_venues, so an agent can route without opening a schema.

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?

Gives concrete example phrasings ('which wallets am I tracking', 'is my Base address included') and names both alternatives with the condition that selects them: get_portfolio for holdings, get_venues for exchange accounts. When-to-use and when-not-to-use are both explicit.

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