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

With annotations already covering read-only/idempotent/non-destructive, the description adds substantial context beyond them: UTC slices 4 hours wide ordered oldest-first, null where nothing was measured, and the pooling semantics (block_time and hashrate pooled over the 24 hours to each slice's end so single-slice luck does not bias them). It also defines the derived series (hashprice_lax, security_budget_lax at today's block pay, mempool_pressure as pending share of a block).

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?

Purpose and time window are front-loaded, followed by metric definitions and then the sibling routing sentence. It is dense and long, but nearly every clause carries information the agent needs to interpret the series; minor compression of the metric list is possible but nothing is filler.

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?

No output schema exists, and the description compensates by enumerating all returned fields with their units and aggregation semantics, including null handling and slice width/ordering. An agent has enough to call the tool and interpret the response without further documentation.

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 'metrics' parameter's enum is already listed in the schema, so the baseline is 3. The description earns extra credit by explaining what each selectable series actually measures, which materially helps an agent decide which metrics to request and interpret the result, plus it restates the default-all behavior.

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 verb+resource (the status page's figures over the last 7 days) and enumerates every returned series, so an agent knows exactly what this tool produces. It also explicitly distinguishes itself from explorer_charts, which covers longer transaction/fee/gas histories.

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 names an explicit alternative for a specific case: 'For longer histories of transactions, fees and gas, use explorer_charts.' That routes the agent away from this tool when appropriate, but it gives no guidance about when this tool is preferred over other siblings such as network_health, mining_stats or mempool_status.

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