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

Annotations already establish readOnlyHint, idempotentHint, and non-destructive behavior, so the safety profile is covered. The description adds the crucial fact that rates in filters are fractions (0.05 = 5%), which is a valuable non-obvious behavioral rule. It does not, however, describe output shape, group ordering beyond what groupBy/topGroups imply, or how empty results behave.

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?

A single sentence, front-loaded with 'Market overview for any filter', followed by the outputs and the fraction convention. No filler and every clause carries information.

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?

Output schema exists, so return values need not be explained, and the description still enumerates the key metrics returned. Combined with annotations and full schema coverage, an agent has enough to call it correctly. The only minor gap is the absence of explicit routing guidance versus sibling aggregate tools.

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 100%, so the schema itself documents the filter fields, groupBy, and topGroups thoroughly. The description only adds the fraction-vs-percentage convention and the default grouping of 'chain' – useful but marginal against a fully documented schema. 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?

The description names a specific verb and resource ('summarize yields', 'market overview') and enumerates exactly what statistics are produced (pool count, total TVL, median, middle-half, TVL-weighted APY, largest pool per group). This distinguishes it cleanly from siblings like search_pools (returns pools) and get_pool (single pool).

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 description implies the tool is for aggregate/market views rather than individual pool lookups, but it never explicitly states when to use this instead of search_pools or compare_pools. No exclusions or selection conditions are given.

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