read_manifest

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

No annotations are provided, so the description carries the burden. It usefully discloses an unexpected guardrail ('Refuses any file not named video_manifest.json') and the return shape ('full envelope'), but says nothing about error behavior, permissions, or what the envelope contains beyond the vague term.

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?

Two tightly written sentences with no filler, and the core purpose is front-loaded before the constraint clause. Every clause earns its place.

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 single-parameter read with no output schema and no annotations, the description covers purpose, provenance, and the naming guardrail adequately. It could note failure behavior or envelope contents, but nothing essential is missing.

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% with a single documented 'path' parameter, so the schema already does the work. The description adds only an implicit naming constraint on the target file, not syntax or format detail beyond what the schema provides, so the baseline 3 is appropriate.

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 (Read) and resource (video_manifest.json) and clarifies the file's provenance ('produced by a previous extract/lookup'), which distinguishes it from the sibling extract_video and lookup_video tools. An agent can identify the operation without opening the schema.

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?

It clearly situates usage after an extract/lookup and states what it returns, implying when to reach for it. It stops short of naming an explicit alternative or saying when NOT to use it, so it is clear context but not full routing guidance.

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