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

Annotations already declare readOnly=true, idempotent=true, destructive=false, openWorld=true, so the safety profile is covered. The description adds the exact endpoint it calls and that it returns that response verbatim, plus the snapshot granularity, but says nothing about rate limits, auth, or data freshness.

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?

Compact and front-loaded, but the opening 'Token Balance History.' merely restates the title and does not earn its place. The remaining two sentences are efficient and informative.

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?

A read-only, well-annotated tool with a full output schema and 100% parameter coverage; the description's job is only to establish scope, which it does. Nothing an agent needs to call it 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?

Schema description coverage is 100%, so all four parameters are already documented in the schema. The description reinforces the resolution semantics ('daily, weekly, or monthly ... over time series') and the USD valuation nature of results, but adds no new detail 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?

States a specific verb and resource: fetching wallet token balance history over time series, with daily/weekly/monthly portfolio snapshots and USD valuations. The wallet-scoped framing implicitly separates it from token-centric siblings like get-token-balance-history-batch, but no sibling is named explicitly.

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?

Usage is implied: the mention of time series and portfolio snapshots over time tells the agent this is for historical balance trends rather than current balances (get-wallet-token-balances). However, there is no explicit when-to-use / when-not-to-use guidance or named alternative.

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