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

With no annotations, the description must carry the behavioral load. It partially does so by revealing the returned dimensions (txs, bytes, usage vs capacity, min fee, total fees) and that a 'busy/normal verdict' is computed, which implies a read-only informational tool. It says nothing about permissions, freshness/refresh cadence, or failure modes.

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 sentences, front-loaded with the resource and followed by the usage trigger; the parenthetical metric list is dense but information-bearing. Minimal waste, though the parenthetical could be trimmed.

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 and no annotations, so the description is the only guidance available. It usefully enumerates the reported metrics, but omits the multi-chain behavior the schema supports and any indication of response shape or units, leaving gaps for a status tool.

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%, so the enum for 'chain' is already fully documented. The description actively narrows that scope by saying 'for BTC', which conflicts with the btc/ltc/doge enum and could lead an agent to believe non-BTC chains are unsupported, so it adds negative rather than neutral value here.

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?

It names a specific resource (mempool congestion) and lists the metrics it reports, so the general purpose is legible. However, it claims the tool is 'for BTC' while the schema accepts btc/ltc/doge, and it never distinguishes itself from the overlapping sibling btc_mempool_summary or btc_fee_estimates, leaving real ambiguity about scope.

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?

The explicit 'When to use: decide whether now is a good moment for an on-chain settlement' gives a concrete decision context, which is better than most definitions. It stops short of naming alternatives (btc_fee_estimates, get_recommended_fee_rate) or when-not to use it, so it does not reach the top band.

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