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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint=false and destructiveHint=false, so safety is covered. The description adds genuine value beyond that: it discloses the exact outbound behavior (one GET to a third-party API) and enumerates failure verdicts such as not_checkable_by_get and no_matching_field, which tell the agent what a null/negative result means.

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 front-loaded sentences: what it does, when to use it, and its runtime footprint. Every sentence earns its place, with only mild redundancy in the trailing "read-only" clause that duplicates readOnlyHint.

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?

An output schema exists, so return-value shape needn't be re-explained, and the description still names the verdict vocabulary needed to interpret results. It is essentially complete, missing only cost/latency or rate-limit expectations for the third-party GET.

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% with both parameters documented (metric tied to get_network metrics, symbol as network ticker), so the schema carries the load. The description adds nothing about parameter semantics or valid value ranges, so 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: it re-reads the upstream API behind a value and reports JSONPath location, relative difference, and a named verdict set. An agent immediately knows this is a source-verification tool, though the description never distinguishes it from the similarly named sibling verify_footprint.

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?

"Use it to check a figure before relying on it" gives a clear triggering condition. There are no exclusions, prerequisites, or comparison to alternatives such as verify_footprint or get_metric_history, so the agent must infer when this is preferable to those siblings.

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