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's job is to add context beyond that. It does: it discloses that results include dot/dash counts, memory tips, and a link to the matching SandiMorse page — content an agent would otherwise not anticipate from the schema. Its only gap is not describing shape or limits of the returned chart.

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?

A single dense sentence that leads with the primary return value and branches into the character-lookup variant, with no filler. It is slightly packed — the link and memory-tip details arrive in the same clause — but nothing is wasted.

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 an output schema present, full schema coverage, and rich annotations, the description only needs to convey purpose and the character-vs-chart behavior, which it does. The absence of explicit sibling routing is the one thing an agent might still want.

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 parameters are already fully documented, giving a baseline of 3. The description adds modest meaning by explaining the purpose of the 'character' path (single code plus counts and tips) and the letter/digit/punctuation buckets, but says nothing about the 'language' parameter's effect beyond what the enum already conveys.

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 states a specific verb and resource: it returns the Morse code chart for letters, digits and punctuation, or the code for a single character with dot/dash counts and memory tips. That clearly marks it as a reference/chart lookup rather than a translation or encoding tool, though it never names the siblings (translate_morse, encode_scout_code) it sits beside.

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?

Usage is only implied: 'Without it the chart is returned' tells the agent that omitting 'character' yields the full chart, which hints at the lookup-vs-chart split. There is no explicit when-to-use guidance, no statement of when to prefer this over translate_morse or morse_practice, and no exclusions.

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