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

Beyond the annotations (readOnlyHint, idempotentHint, destructiveHint), the description discloses several non-obvious behaviors: it 'returns 404 when the filing has no comprehensive-income statement,' costs '28 credits, debited even when the filing is missing, has no such statement, or is not an SEC filing,' and states that light_weight_mode reduces the payload. These are important operational details an agent would not infer from the schema or 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 moderately long but every sentence carries unique information: purpose, identification, shortcut relationship, 404 behavior, jurisdiction, cost, light_weight_mode, and endpoint. It is front-loaded with the core purpose and follows a logical order. The trailing 'POST ...' and documentation pointer are arguably extra but not fluff.

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 tool with six parameters and no output schema, the description covers identification methods, error behavior, cost, jurisdiction, and payload mode. It gives a high-level view of the response ('line items with values and periods') but doesn't detail response structure or potential pagination. Given that the schema covers all parameters and annotations cover safety, this is a complete-enough definition for an agent 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 coverage is 100%, so the baseline is 3, but the description adds relational semantics: it explains that filing_id is an alternative to ticker + fiscal_year, that quarter is optional, and that light_weight_mode yields a leaner payload. This grouping and conditionality is not evident from individual parameter descriptions alone, pushing the score above baseline.

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 opens with a specific verb and resource: 'Return the filing's Statement of Comprehensive Income — its extracted line items with values and periods.' It further distinguishes itself from siblings by explicitly stating it is a 'fixed shortcut for get_filing_statement(statement_type='Comprehensive Income')' and that it does not take role_label or statement_type, so an agent can immediately tell it apart from get_filing_statement and get_income_statement.

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 provides explicit identification guidance (filing_id or ticker + fiscal_year) and clarifies the shortcut relationship to get_filing_statement. It also gives a clear exclusion: 'Available for SEC filings only — other jurisdictions coming soon,' and warns about the 404 case. However, it doesn't explicitly contrast with get_income_statement or say 'use this when you need comprehensive income instead of the general statement tool,' though that is implied by the shortcut phrasing.

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