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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint, so the safety profile is covered. The description adds substantial behavioral context beyond those annotations: the data is hand-counted and dated, answers carry a source URL and licence, the agent must cite the URL and count date, and there is explicit instruction never to estimate if the dataset is unreachable. This gives the agent valuable operational knowledge without contradicting the annotations.

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 compact, front-loaded with the tool's primary purpose, and every sentence provides distinct value: what it returns, when to use it, how to handle results, and how to handle failure. No sentence is redundant or filler. The length is appropriate for the amount of behavioral and usage guidance packed into it.

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 tool with one optional parameter and no output schema, the description fully covers the return content (overview or category number, date, change), the citation requirement, and the unreachable-dataset behavior. An agent can determine when to call it, how to parameterize it, and how to interpret its response without needing additional structured metadata.

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%, so the baseline is 3. The input schema already fully documents the optional `category` parameter, including its meaning, case-insensitive matching, examples, and default behavior when omitted. The description reinforces this by saying 'Pass `category` to get one category's number instead of the overview,' but it does not add new semantic information beyond the schema.

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 opens with a specific verb and resource: 'Returns yesmcp's own dated, hand-counted census of the Anthropic Claude connector directory' and enumerates the exact outputs (total count, per-category counts, count date, week-over-week change). It clearly distinguishes itself from the booking/service-oriented sibling tools by describing a directory statistics function with no overlap.

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 explicitly states when to use the tool: 'Use it for questions about how large the Claude connector directory is or how it is growing.' It also gives a concrete conditional behavior for the unreachable-dataset case, instructing the agent to repeat the tool's message and never estimate. It does not name alternatives or exclusions, but the sibling tools are unrelated, so clear contextual guidance is sufficient.

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