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

Annotations already flag destructive and open-world, and the description adds real value beyond them: it discloses inherited Codex login/model, incremental progress on long tasks, and — most importantly — that a failed or cancelled run may still have mutated files. What is missing is any sense of return payload beyond threadId or of concurrency/rate behavior.

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?

Five short sentences with the identity, the return value, and the two most consequential settings front-loaded. Every clause carries actionable information; the retry warning is correctly placed last as a caveat.

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?

Covers the essentials for a 10-parameter, mutation-capable, no-output-schema tool: what it returns, what it authenticates as, and what safety posture to pick. The nested config object with eight undocumented sub-fields is the one area neither the description nor schema explains.

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 90%, so the baseline is 3; the description pushes higher by adding selection guidance for sandbox (workspace-write for edits) and cwd (the project directory). It adds nothing for add_dirs, timeout_seconds, images, or reasoning_effort, which the schema already documents.

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 verb and resource ("Run a task in a new Codex conversation") and immediately names the handoff sibling by declaring it returns threadId for codex-reply. An agent can distinguish this from codex-reply and codex-sessions without opening either 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?

Gives concrete operational guidance: set cwd to the project, use sandbox=workspace-write for edits, and inspect before retrying after a failure. The threadId mention implies the follow-up path through codex-reply, though it never states explicitly when to prefer codex-reply over starting a new conversation.

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

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

Annotations already declare destructiveHint=true, openWorldHint=true and non-idempotent, so the risk profile is covered upstream. The description adds two genuinely new facts — conversations survive restarts and only one turn may run per conversation (a concurrency constraint) — but says nothing about what gets mutated on disk or how errors surface during a long run.

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?

Three short sentences, front-loaded with the core purpose followed by the required handle and the concurrency limit. No filler and nothing buried.

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 12-parameter, nested-config, long-running tool with no output schema, the description never indicates what comes back — the reply text, a new threadId for subsequent turns, or status. The agent can call it, but can't predict or chain the result from the description alone.

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 75%, and the two undocumented parameters (`threadId`, `conversationId`) are precisely the ones the description explains: threadId is obtained from `codex` and conversationId is the legacy form. That is real added meaning beyond the schema, though the description doesn't touch the 12 params overall.

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?

"Continue a Codex conversation across MCP/Claude restarts" gives a specific verb (continue) plus resource (Codex conversation), which implicitly separates it from the sibling `codex` (start) and `codex-sessions` (list). It stops short of naming those siblings explicitly, so the differentiation must be inferred.

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?

"Pass threadId from codex" tells the agent exactly where the required handle comes from and thus when this tool is the right one, and the legacy `conversationId` fallback is flagged. No explicit exclusion (e.g. "use codex to start a new conversation") is stated, so it's clear context rather than complete routing guidance.

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

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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and closed-world, so safety is covered. The description adds genuine context beyond them: results are metadata only (no message bodies) and the listing is scoped to threads this bridge created. It does not state default size or ordering, leaving a small gap.

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?

One sentence, front-loaded with the action and resource, with the qualifier and the downstream use case packed into parenthetical and trailing clauses. 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?

For a simple, fully annotated, closed-world read with no output schema, the description covers what is returned at a high level (metadata, threadId) and why it exists. Only the pagination/limit behavior an agent would need for large histories is unaddressed.

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 single 'limit' parameter has 0% schema description coverage, so the description carries the full burden and says nothing about it — no default page size, no mention of the 1-100 range, no ordering semantics. With low coverage and no compensating text, this is a clear gap.

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 verb+resource ('List recent conversations created by this bridge'), scopes it to bridge-created threads, and immediately qualifies the payload as metadata-only. It also names the sibling it feeds (codex-reply), so an agent can distinguish it from codex and codex-status without opening any 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?

The 'to recover threadId for codex-reply' clause gives an explicit use case and routes the agent to the consuming sibling. There is no explicit exclusion (e.g., when to use codex-status instead), which keeps it short of a 5.

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

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

Annotations already declare the tool is read-only, idempotent, non-destructive, and closed-world. The description adds useful behavioral context by enumerating the specific checks performed and clarifying that no model request is made, which is valuable beyond the annotations, though it does not describe the response shape.

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 a single front-loaded sentence with no filler. Every listed item contributes to explaining what the status check covers.

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 zero-parameter, read-only status tool with rich annotations, the description gives enough scope to invoke it correctly. The main minor gap is that return values are not described and no output schema exists, but the enumerated checks provide sufficient operational 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 tool takes zero parameters, so there are no parameter semantics to document. Baseline 4 applies because the schema requires no compensation and the description introduces no misleading parameter behavior.

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 ('Check') and a precise set of resources: Codex executable, compatibility, login state, fallback runtime, and active tasks. It is clearly a status/diagnostic tool rather than a task invocation tool, but it does not explicitly differentiate itself from siblings like codex, codex-sessions, or codex-reply.

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 phrase 'without making a model request' implies this tool is for cheap diagnostics before invoking the model, but the description never states when to use it instead of siblings or when not to use it. Usage is inferable rather than explicit.

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