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

Annotations already declare read-only, idempotent, non-destructive, closed-world behavior, so the safety profile is covered. The description adds genuinely non-structured context: a flat 10-credit cost, the POST endpoint, and return-field semantics (statement_type is null for non-financial header blocks, a list when a block combines statements). It stops short of pagination or ordering details.

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?

Front-loads the verb and the return payload, then scope, cost, and follow-up, with no filler sentences. It is a fairly dense paragraph, but every clause carries information relevant to selection or invocation.

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?

With no output schema, the description takes on the return-value burden and handles it by enumerating the fields and their edge cases. Combined with scope rules, credit cost, endpoint, and the follow-up tool, an agent has everything needed to call it correctly.

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%, with detailed per-parameter descriptions already present. The description restates the scope rule (filing_id OR ticker + fiscal_year, optional quarter) but adds no syntax or format detail beyond what the schema supplies, so 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+resource ('list every statement block for one filing') and enumerates the returned fields with their semantics (block_index, statement_type, role_label). It also distinguishes itself from the sibling get_filing_statement by framing this as discovery and that tool as the row-label detail step.

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?

Names the entry condition ('Discovery') and gives the scope selector (filing_id OR ticker + fiscal_year, optional quarter), plus an explicit follow-up tool. It does not spell out when-not to use it versus other statement getters, but the workflow routing is clear.

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