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

Beyond the annotations (which already cover safety/idempotency), the description adds real behavioral value: no credit cost, the BING_WEBMASTER_API_KEY requirement, and two named failure modes with their reason strings. The return shape is only referenced indirectly ('the same Feed shape as one entry from Bing's GetFeeds list'), which leaves some ambiguity since that list isn't a visible sibling.

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?

One compact paragraph, front-loaded with the operation and its scope, then cost, auth, and error behavior in descending priority. Every sentence adds information; only the vendor-list reference slightly muddies the structure.

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 carries the return-shape burden and does so only by reference to Bing's GetFeeds entry type. Auth, cost, and error states are covered, so an agent can invoke it correctly, but there is no pagination or response-field detail.

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% and both parameters are documented in the schema (feedUrl format/purpose, projectId sourcing from list_projects). The description adds no syntax, format, or constraint detail beyond what the schema already states, so the baseline of 3 applies.

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 names a specific verb+resource (fetch one Bing feed's details for a given feed URL) and scopes it precisely to 'one specific feed URL on a project's matched site.' This distinguishes it from siblings like submit_bing_feed (write) and list_bing_sites, and the title annotation reinforces the same framing.

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 gives clear operating context (free, read-only, BYO key) and the conditions that produce failure results ('not_configured', 'no_matching_site'), which help an agent anticipate prerequisites. It does not, however, explicitly state when to prefer this over alternatives such as get_bing_site_overview or when a feed URL is unavailable.

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