gdex_feature_metrics

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

Annotations already declare readOnlyHint=true and openWorldHint=false, but the description adds substantive detail beyond them: it enumerates what is not collected (accounts, trades, coins, amounts, codes), states nothing leaves the machine, and discloses that GDEX_METRICS=off disables counting, which explains zero or missing results. Return format is only gestured at ('replay completion and referral conversion reported separately'), which keeps it short of 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?

Two tightly packed sentences front-load the purpose, then the privacy guarantee and the environment toggle, with no filler. The colon construction keeps the feature list compact. It is efficient, though the privacy enumeration is slightly long relative to the core claim.

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?

For a simple read-only tool with no output schema, the description should carry the return shape, and it only hints that replay completion and referral conversion come back separately without naming fields or units. Combined with the unmentioned sinceDays parameter, an agent still has gaps about what the response actually contains.

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 0% and the single parameter sinceDays is never mentioned in the description, so its time-window semantics must be inferred purely from the name and the 1-365 bounds in the schema. For a metrics tool whose numbers depend entirely on the lookback window, that is a meaningful gap the description does not compensate for.

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 states a specific verb and resource ('Aggregate usage counts for trade replay, practice challenges and invites') and scopes it to 'this machine', so an agent knows exactly what data it returns. It never names a sibling tool or explicitly contrasts itself with the action tools (gdex_replay_trade, gdex_invite), though no sibling offers metrics, so the distinction is implicit rather than spelled out.

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 implied: an agent can infer it should call this to read cumulative feature usage rather than to perform replays, challenges or invites. There is no explicit when-to-use statement, no exclusions, and no pointer to the sibling action tools that generate the counts.

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