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

With no annotations, the description carries the full disclosure burden. It does add useful context: the upstream data source (DefiLlama), the caveat that fees/revenue exist only 'where available' (signaling nullable fields), and a 'not financial advice' disclaimer. It does not confirm read-only behavior, error handling for unknown protocols, or rate limits, so it is informative but incomplete.

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?

The purpose is front-loaded in the first clause before the long field inventory. The dense field list is justified because there is no output schema, and the two trailing sentences are short and earn their place.

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 must convey the return shape, and it does so thoroughly via a field list plus source attribution and availability caveats. The remaining gaps are behavioral (unknown-slug handling, exact-match ambiguity against find_protocol) rather than missing return information.

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 the single parameter already documents the slug-or-exact-name format with examples. The description's 'by slug or name' restates the schema rather than extending it (no case sensitivity, aliasing, or disambiguation guidance), so the baseline 3 for fully covered schemas 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?

The description names a specific action and resource ('Compact DeFi protocol brief') and enumerates exactly what the brief contains (TVL, 1d/7d/30d change, chain breakdown, audits, fees/revenue), so an agent knows precisely what comes back. It implies exact-match lookup ('by slug or name'), which distinguishes it from the search-oriented sibling find_protocol, but that contrast is never made explicit.

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 only implicit: the 'by slug or name' phrasing hints you need an exact identifier rather than a search term. It never states when to prefer this over find_protocol, nor what happens if the slug is unknown or ambiguous, leaving the agent to infer the lookup-vs-search split.

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