Readwise MCP HTTP Server

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

With no annotations provided, the description carries the full burden. It discloses that the tool returns data (not a mutation) and specifies the return fields (text, note, tags, book title, author, URL), which is useful behavioral context. However, it doesn't mention error handling, permissions, or rate limits, leaving gaps for a read operation.

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 front-loaded with the core purpose in the first sentence and details return values in the second. Every sentence earns its place with no wasted words, making it highly efficient and well-structured for quick understanding.

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?

Given 1 parameter, no annotations, and an output schema (which handles return values), the description is mostly complete: it states the purpose, usage context, and key return fields. However, it lacks error cases or behavioral nuances (e.g., what happens if the ID doesn't exist), leaving minor gaps in context.

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 input schema has 1 parameter with 0% description coverage, but the description compensates by clarifying that 'highlight_id' is used to 'Get a single highlight by ID'. This adds meaning beyond the bare schema, though it doesn't detail format constraints (e.g., integer range). Since there's only 1 parameter, the baseline is high.

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 the specific action ('Get a single highlight by ID') and resource ('highlight'), distinguishing it from siblings like 'list_highlights' (which returns multiple) and 'search_highlights' (which filters by criteria). It explicitly includes 'book metadata included' to differentiate from potentially simpler retrieval tools.

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 usage when needing a specific highlight by its ID, with context from 'single highlight by ID' suggesting it's for detailed retrieval rather than listing or searching. However, it doesn't explicitly state when not to use it (e.g., vs. 'list_highlights' for multiple items) or name alternatives, keeping it from a perfect score.

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