get_song

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

With no annotations, the description carries the full behavioral burden. It does well on the return shape, spelling out that the result includes title, artist, font, column width, gutter, and chord-lyric pairs, but it says nothing about read-only semantics, failure behavior for an unknown slug, or how project_dir resolution affects the lookup (that detail lives only in the schema).

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 front-loaded sentence with the verb and key identifier first, followed by the parenthetical payload list. Every clause earns its place because the payload detail substitutes for a missing output schema.

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 simple two-parameter read with no output schema, the description supplies the most important missing piece: what the returned AST contains. The remaining gap is error/not-found behavior and explicit read-only framing, which are minor for this complexity level.

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 both slug and project_dir are already documented in the schema, and the description only echoes the slug-based lookup. Baseline 3 applies since the description adds no syntax, format, or fallback meaning beyond the structured fields.

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 ("Retrieves") and resource ("full structured AST for a song by slug") and enumerates the returned components, so the agent knows this is a single-song fetch rather than a listing. It does not explicitly name the sibling it differs from (e.g., list_songs or get_songbook), which keeps it just short of a 5.

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 implied by "by slug" — use this when you already know the song identifier — but there is no explicit when-to-use/when-not guidance and no pointer to alternatives like list_songs for discovery. An agent must infer the selection criteria from the sibling names alone.

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