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

Annotations already declare readOnly, idempotent, openWorld, and non-destructive, so the safety profile is covered. The description adds genuinely useful context beyond that: the corpus is a 'bounded, self-hosted mirror', it enumerates what is returned, and it discloses a real limitation ('does not expose licensed CUSIP identifiers').

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?

Three sentences, front-loaded with purpose, then return fields, then use cases and a limitation. The return-field enumeration is long but earns its place given the absence of an output schema; no sentence is pure filler.

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 usefully enumerates return contents (symbols, names, coverage, observation counts, max balance, pagination, snapshot hash, provenance), which an agent would otherwise lack. Combined with the CUSIP limitation, it covers what is needed for correct invocation, though it does not clarify pagination semantics in depth.

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 already documents query, limit, offset, and response_format, giving a baseline of 3. The description only loosely references pagination and returns; it adds no syntax, format, or constraint detail beyond what the schema supplies.

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 (Search) and resource (ticker symbols and issuer names) within a clearly scoped corpus (SEC fails-to-deliver files in a bounded self-hosted mirror). The 'resolve a symbol before a lookup' clause hints at its position relative to lookup-style siblings, but no sibling tool is named explicitly, so it stops short of full differentiation.

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?

Provides three concrete use-case examples ('find the FTD ticker for GameStop', 'which SEC fail records mention Tesla?', 'resolve a symbol before a lookup') that give an agent clear trigger conditions. There are no explicit exclusions or named alternative tools, so it is context-rich but not exhaustive.

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