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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint and destructiveHint=false, so the safety profile is covered. The description adds genuinely new behavior beyond that: a 15-minute in-memory collection cache, returned coverage metadata, and the fact that accounts include connections with zero transactions — a non-obvious data-shape caveat.

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?

Four short sentences, front-loaded with the operation and scope, with no redundant restatement of the name or title. The prerequisite call is placed last, where an agent will read it before invoking.

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 partially compensates by mentioning coverage metadata and the accounts-without-transactions case. It is nearly complete for a 4-parameter read tool, but the absence of date-format and limit guidance leaves a small gap.

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%, so the description must carry the parameter burden. It clarifies that sql is a SELECT-only SQLite query and that from/to delimit a UTC period, but gives no date format and never mentions the limit parameter or its 200-row cap, leaving meaningful gaps.

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 dialect (read-only SQLite SELECT) over named resources (accounts and transactions) scoped to a UTC period. It also distinguishes itself from the sibling by naming pluggy_schema as a prerequisite rather than an alternative query path.

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?

Gives explicit sequencing guidance ("Call pluggy_schema before computing totals") and implies the tool's role is querying for aggregates over a period. It does not, however, state when NOT to use it or contrast it with a filtering alternative, since pluggy_schema is the only sibling.

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

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

Annotations already declare read-only, idempotent, non-destructive, and open-world behavior. The description adds a useful security note ('Does not access secrets'), but it does not disclose return format, scope of schema coverage, or other behavioral context beyond the annotations.

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?

The description is very short and front-loads the key content categories. Every sentence is brief, though the extreme terseness leaves some ambiguity that a slightly fuller structure could resolve.

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 zero-parameter, read-only metadata tool with rich annotations and no output schema, the description covers the broad content areas and a security caveat. However, it does not clarify the relationship to pluggy_query or exactly what the schema output contains, leaving an agent to infer key context.

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?

The tool takes zero parameters, so there is no parameter semantics burden. Per the rubric, a zero-parameter tool receives a baseline of 4 regardless of description detail.

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 lists content categories (SQL fields, semantics, transaction limitations) but does not state a clear action such as returning or describing a schema. The name and title imply it is a schema tool, but the description itself is vague about what it does. It also does not distinguish this tool from the sibling pluggy_query.

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?

There is no explicit guidance on when to use this tool versus pluggy_query or any other alternative. The phrase 'transaction limitations' weakly implies it should be consulted before querying, but no condition or alternative is stated.

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