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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), so the description only needs to add context. It does: it discloses the enumeration of valid skill names, that omitting name lists the catalog, and that this is not the dashboard Skills page. Return shape when a skill is fetched is only loosely implied.

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?

Four sentences, front-loaded with the what, then the when, then the parameter behavior, then a one-line disambiguation. No sentence is redundant against another, and the most decision-relevant information (when to call) comes early.

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?

One optional parameter, full schema coverage, no output schema, read-only annotations – the description supplies the calling preconditions and the value set, which is everything needed to invoke correctly. The only omission is any differentiation from modem_docs among the siblings.

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 the baseline is 3, but the description goes beyond the schema by enumerating the five catalog values ('search-modem', 'agent-runs', 'write-tools', 'install-feedback', 'automations'), which the schema only gestures at with a single example and no enum. That materially reduces wrong-value calls.

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 resource and function: skill documents that teach usage of this server's tools, with the referent 'THIS Modem MCP server' pinned down and an explicit disambiguation from the dashboard Skills page. It does not, however, distinguish itself from the sibling tool modem_docs, which an agent could reasonably confuse it with for 'how do I use this server' questions.

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?

Gives concrete trigger conditions (before the first search_modem, modem_agent_invoke, or write-tool call; when unsure which tool to use) and explains the omit-name behavior. The gap is that it never contrasts itself with modem_docs, so the agent has no routing rule between the two documentation-ish tools.

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