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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the description's added value is the non-obvious data freshness split: metrics are lagged one day while ecosystem counts are current, and the source is free AlphaGrowth data. It doesn't disclose return shape, pagination, or whether unknown slugs error or return empty, which are the remaining behavioral gaps.

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 tight sentences, front-loaded with the tool's identity, then the freshness caveat (the highest-risk misreading), then the cross-reference. No filler and nothing redundant with the schema or annotations.

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?

There is no output schema, so the description carries the burden of describing return content, and it does so by enumerating the metric families returned. Combined with the lag caveat and the sibling cross-references, an agent has everything it needs to call this correctly.

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% and the single `slug` parameter is already documented with an example and the reference to `chains`, so the schema does the heavy lifting. The description adds only the useful note that the same slug is reused by project_metrics. Baseline 3 is appropriate.

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 the specific resource (a blockchain's AlphaGrowth chain-compare metrics) and enumerates exactly which values are returned: TVL, transactions, price, social numbers, and ecosystem counts. It explicitly distinguishes itself from project_metrics, which carries the chain's current price, so an agent can route between them 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?

It states the temporal condition that selects this tool (daily snapshots as of `date`, one day ago UTC) and names the alternative for current values (project_metrics with the same slug), plus points at `chains` for the slug. What it doesn't do is frame a general when/when-not rule for historical trend lookups, which keeps it short of a 5.

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