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

With no annotations provided, the description carries the full burden of behavioral disclosure. It mentions it 'Mirrors account_statement_infographic' and lists included metrics (corpus size, median t+15m impressions, etc.), but it does not state whether the tool is read-only, whether it requires OAuth or patron credentials, what side effects occur, or how the SVG is returned. The 'Patron:' prefix hints at access restrictions but is ambiguous.

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?

The description is extremely concise: two sentences that front-load the purpose and then add relevant detail about theme and content. Every sentence contributes value, with no redundant filler or vague jargon.

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?

The description gives a good overview of the output content and theme, but it omits critical context about authentication, prerequisites, and parameter usage. While the presence of an output schema reduces the need to describe return values, the tool still requires npub and dpop_token, and the description doesn't explain how these are used or why they are needed. This leaves the tool somewhat incomplete for an agent to invoke confidently.

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?

The description provides no explanation of the 'npub' and 'dpop_token' parameters beyond what the schema already gives for npub. The 'dpop_token' parameter is entirely undocumented in both the schema and description, leaving a significant gap. Since schema coverage is only 50%, the description should have clarified the role of the token but did not.

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 clearly states this tool produces an 'SVG infographic of post performance' with a specific gold-steel theme, which identifies the resource and output type. It also references the sibling 'account_statement_infographic' to give context, but it doesn't explicitly state the action verb (e.g., 'generate' or 'create') nor directly contrast with 'excalibur_post_performance' for data vs. infographic.

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?

The description implies similarity to 'account_statement_infographic' but provides no explicit guidance on when to use this tool versus alternatives like 'excalibur_post_performance' or other infographic tools. There is no mention of scenarios, prerequisites (e.g., being a patron), or exclusions, leaving the agent to infer usage context.

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