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

Annotations cover readOnly/openWorld/destructive, so the bar is lower. The description adds real behavioral context: data source (Bing's link index), the two distinct output shapes, and paging behavior with totalPages. It doesn't mention rate limits or whether results are delayed/cached, but covers the key operational traits.

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 resource and data source, then the two modes, then paging. Zero filler; every sentence carries distinct information.

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?

No output schema exists, so the description must convey return shape - it does via 'link count each' and 'anchor text'. Paging is covered. Missing are error/edge cases (e.g., unverified site, empty index) and result limits per page, but overall adequate for a read-only lookup tool.

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 baseline is 3. The description adds meaning beyond schema by explaining the semantic effect of the optional url parameter (mode switch) and how paging relates to totalPages, which the schema's terse 'Result page, starting at 0' doesn't convey.

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 (backlinks / who links to the site) and scopes it to Bing's link index. It distinguishes itself from search-console siblings like bing_top_pages by defining behavior in both url-absent and url-present modes.

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?

Clearly explains the two usage modes: without url returns site-level pages with inbound links; with url returns specific referring pages and anchor text. No explicit exclusions or named alternatives, but the mode selection is fully specified.

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