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

Annotations already declare readOnlyHint and openWorldHint, so safety is covered. The description adds genuine behavioral context beyond that: the exact return shape and the non-obvious gotcha that 'title' is the first detected heading, not the HTML <title>. Missing are auth/rate-limit or failure-mode notes, which keeps it off 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?

Front-loaded with the core distinction (parsed markup vs raw HTML) before the return details, and every clause carries information. The long parenthetical about the title field makes one sentence dense and slightly harder to scan, but nothing is wasted.

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?

An output schema exists, so restating return fields is partly redundant, but the clarification of the ambiguous 'title' field is exactly the kind of thing a schema cannot convey. With only two params, readOnly/openWorld annotations, and this level of detail, an agent has enough to invoke it correctly; only the required 'url' semantics are unaddressed.

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 parameter meaning. It does explain 'workspace' well ('Slug des Kunden-Workspace, optional bei nur einem Workspace'), but 'url' is left completely undocumented despite being the required parameter — no format, absolute-URL, or scope hints.

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 ('Strukturierter Seiteninhalt ... geparstes Markup statt Roh-HTML') and enumerates what is extracted (headings, paragraphs, links_count). It explicitly differentiates from siblings dfs_raw_html and dfs_onpage_instant, so an agent can pick it without opening another schema.

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 alternative for one concrete case: 'title ... NICHT das <title>-Tag — dafuer dfs_onpage_instant'. That is a real routing instruction, but it only covers the title-tag case and gives no guidance on when to choose this over dfs_raw_html or dfs_onpage_crawl.

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