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 value beyond that by disclosing return shape ('publication and ingestion timestamps plus source links'), which matters since there is no output schema. It does not mention pagination or rate limits, keeping it short of a 5.

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 the core action before the filter and code details. Every sentence contributes; only the somewhat long topics enumeration risks being a run-on.

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 read-only, zero-required-param tool with no output schema, the description covers the topic code vocabulary and the returned fields well enough to call it correctly. The main remaining gap is the meaning/defaults of limit and the feed enum, which it never touches.

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 0%, so the description must carry the param burden. It does map 'text, tickers, topics, feed' to the corresponding parameters and, importantly, decodes the opaque topics vocabulary (mna, cb, energy, reg, crypto, earn, ipo, or category id) that the schema cannot express. It leaves limit and the feed enum values ('latest/top/breaking') unexplained, so compensation is partial.

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: 'Search or list market-news stories', with the filterable dimensions enumerated. It is clearly a news-retrieval tool, but it never positions itself against siblings like social.search_posts or market.search, which also return text content.

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?

Usage is implied by the enumeration of filters, so an agent can infer 'use this to pull news by feed/text/ticker/topic'. However, there is no explicit when-to-use, no exclusions, and no routing to alternatives despite several search-like siblings.

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